It’s ten past nine on a Sunday night. The kids are finally down. You’re staring at your phone watching those three dots pulse as your ex types, deletes, types again. The message that finally lands contests the drop-off time. Or questions what you fed the kids for dinner. Or informs you, casually, that they’ve booked a trip that eats into your weekend.
Your chest tightens. There’s a cold spike in your stomach. You can feel your jaw setting.
You’ve done the reading. You’ve downloaded the co-parenting app. You’ve drafted the response three times, sanded the edges off it, kept it “clinical” like every custody coach on the internet told you to. You’ve read the articles about boundaries. You’ve made a spreadsheet. You’ve forwarded emails to your lawyer.
And still, every Sunday night, you are here. Braced. Rehearsing arguments in the shower. Losing sleep. Living with a low-grade dread that never quite lifts.
I’ve been a couples therapist for over seventeen years. I want to say something that will probably annoy the boundary-setting industrial complex: rigid boundaries and co-parenting apps my arse. Not because you don’t need agreements. You do. But because the fantasy that a tighter schedule and a colder tone will finally give you peace is exactly the fantasy that keeps you stuck.
You are not dealing with a logistical problem. You are dealing with two nervous systems that used to be a base camp for each other, and are now biologically tethered through the child you both love, running survival strategies against each other in the driveway.
Let’s look at what’s actually happening under the waterline.
Recognize yourself in this?
Talk to Figlet about your co-parenting dynamic right now. AI relationship coaching grounded in Figs O’Sullivan’s work, LMFT. Free to start, no credit card.
The Dismantled Base Camp That Won’t Let You Go
Which pattern is running your relationship?
Take the free three minute quiz and meet the creature behind the cycle you keep getting stuck in.
Human beings are wired from infancy to need a co-regulating other. That wiring does not switch off when the marriage ends. Grounded in attachment theory, we know that adult partners function as each other’s primary regulators, the way a caregiver regulates an infant. When that primary bond ruptures, the base camp is dismantled.
But if you share a child, you cannot walk away clean. You remain biologically and somatically tethered through the little person who belongs to both of you. Your two nervous systems are still, whether you like it or not, running signals through each other.
This is the part almost every “boundary” article misses. When your ex sends the passive-aggressive text about pickup, your body does not process it as a schedule conflict. It processes it as a threat to your standing as a parent, to your child’s wellbeing, to your very legitimacy. Your amygdala fires before your rational brain gets a vote. Cortisol dumps. You are, in that moment, no longer negotiating logistics. You are fighting for survival.
And so are they.
This is why the custody app doesn’t save you. The app assumes you are two rational adults exchanging information. In reality, you are two dysregulated attachment systems exchanging alarm signals through a piece of software. The software cannot regulate what the body has not.
From Empathi’s own research: in 58,221 completed relationship assessments, 74.1% of the 6,159 couples where both partners completed were in the pursue-withdraw cycle. Both partners typically describe the other as the one withdrawing.
The Two Ancient Questions Underneath Every Co-Parenting Fight
I tell every couple I work with, whether they are together or not, that the bonded body only ever runs two questions. Never in words. Underneath every argument about the phone, the tone, the schedule, the school pickup, the birthday party invite list, your nervous systems are running the same ancient pair of queries.
Are you there for me? Am I enough for you?
Divorce does not erase these questions. It sharpens them. Now the questions are not about you as a partner. They are about you as a parent, and about whether you are being seen as one.
When your ex texts to inform you they’ve enrolled your son in soccer without asking, your nervous system does not hear “logistics.” It hears: you don’t matter here. You are not a real parent to this child. I have erased you.
When you push back with a firm boundary about needing to be consulted, their nervous system does not hear “reasonable request.” It hears: you are failing. You are a bad parent. You are unacceptable.
Two people, both drowning, both hearing the same threat, both moving in opposite directions to survive it. One reaches for control through structure and rules. The other retreats behind stonewalling or blows up the agreement to prove they cannot be controlled.
This is the pursue-withdraw waltz you probably danced in the marriage. It doesn’t stop at the courthouse. It just changes venues.
What Your Ex Is Actually Defending Against (And What You Are)
Here is the piece I almost never see written about anywhere else. When your ex violates a co-parenting agreement, when they show up late, forget the school form, book the vacation on your weekend, undermine your rule about screen time, they are not usually doing it to hurt you.
They are doing it because your boundary, however reasonable, has landed on their body as a verdict of parenting failure.
The somatic ledger inside them, the running record of every moment they’ve felt like a bad parent since the day the child was born, gets touched. And the burning shame of being a bad father or a bad mother is so intolerable that their body contracts and deploys what I call their Representative. The polished mask. The cold rigid text. The lawyer email. Anything to get some short-term relief from that unbearable feeling of inadequacy.
You, on the other hand, are running your own script. Every violation, every late drop-off, every unilateral decision touches your own ancient wound. Are you there for me? Am I a priority here? Do I matter? Am I safe? You reach harder. You get more precise. You document more. You escalate.
Two people locked in a Waltz of Pain, each one’s protective move confirming the other’s deepest fear. Your ex retreats and violates the agreement, which confirms your fear of not mattering. You get tighter with the rules and the paper trail, which confirms their fear of being an unacceptable parent.
The custody schedule is not the fight. The custody schedule is the courtroom where the real, ancient fight gets litigated over and over.
The Child’s Nervous System Is Keeping the Real Ledger
Now here is the part that will probably land hardest. Because we haven’t talked yet about the person actually paying the cost of this.
Your child.
Children are highly sensitive biological organisms who read the nervous systems of the adults around them. Long before they have language for it, their body knows whether Mom and Dad are safe with each other. Their somatic ledger, the same one all of ours have, maintains an incorruptible record of every driveway pickup where the air was thick with unspoken threat.
The silent tension in the handoff is more terrifying to a child than an open argument. An open argument at least has a shape. It ends. The silent, polite, cold cold war between two parents who “keep it civil for the kids” is a fog the child cannot escape and cannot name.
This is why parallel parenting behind massive walls, while sometimes necessary in the short term, cannot be the long-term answer. Your child does not need you to be married. Your child does not need you to be best friends. Your child needs your two nervous systems to be regulated enough in each other’s presence that they can breathe.
I want to be careful here. I am not asking you to be endlessly generous with someone who has genuinely harmed you. I am asking you to notice that your child’s window of tolerance is being shaped, right now, by whether you and their other parent can find any ground of co-regulation at all.
What Co-Parenting Boundaries Actually Are (And What They Are Not)
Here’s what I mean when I say boundaries and co-parenting apps my arse. I don’t mean don’t have agreements. Of course you need agreements. Written, specific, mutually understood agreements about time, money, medical decisions, school choices, holidays.
What I mean is that a boundary is not a wall.
A boundary is a clear internal knowing of what you can and cannot sustain, expressed to another person from a regulated place. A wall is a defensive structure built by a nervous system in threat.
Most of what people call boundary-setting in co-parenting is actually wall-building dressed up in therapy language. It sounds like: “I’ve set a boundary that you don’t contact me except through the app.” Which may be genuinely necessary. Or it may be a wall you built because your body could not hold the possibility of hearing their voice.
The difference matters. A boundary from a regulated place can be held with warmth. A wall from a dysregulated place always leaks. The wall gets breached, you rage, you double-thick the wall, they breach it again, and around and around you go.
Real co-parenting boundaries have three properties. First, they are about the child, not about winning. Second, they are held from a place where your nervous system is not on fire. Third, they leave room, always, for the possibility that the other parent is a wobbly, frightened human being trying not to fail at the most important thing in their life.
If you want a place to start naming your own pattern in this dance, you can take the free Figs Quiz.
Turning the Flashlight Around
There is a move I ask every co-parent to try. It is deceptively simple and almost impossibly difficult.
Take the flashlight of your awareness, the one that has been aimed like a spotlight at your ex’s failures, and turn it around. Aim it at what is happening in your own body right now.
Not the story about them. The sensation in you.
The tightness across your chest when the text arrives. The heat in your face. The cold in your hands. The way your throat closes. The specific memory that gets touched, of being unseen, unheard, dismissed, controlled, humiliated, erased.
This is what I call moving from the Story of Other to the Experience of Self. It is the single most powerful thing you can do in a high-conflict co-parenting dynamic. Not because it fixes your ex. It doesn’t. But because it is the only move that gets your prefrontal cortex back online. And with your prefrontal cortex back online, you can respond instead of react.
I have watched this move change the trajectory of co-parenting relationships that looked, from the outside, completely unsalvageable. Not into friendship. Not into a Hallmark card. Into something quieter. Two people who can stand in the driveway on a Sunday evening and not send each other’s nervous systems into war.
Ready to work on this?
Figlet is AI relationship coaching grounded in attachment science and Figs O’Sullivan’s clinical work, LMFT. First messages free, no signup.
A Practice-Room Story
A few years ago I worked with two co-parents. A doctor and a founder. Divorced two years. Sharing a seven-year-old. They came in because their son had started having stomachaches every Sunday night before the switch.
She was furious. He was constantly violating the schedule, bringing their son back forty minutes late, changing plans last minute, texting her critical notes about the boy’s diet under her roof. She wanted tighter boundaries. She wanted him locked out of decisions. She had a lawyer on speed dial.
He was cold and rigid in session. Answering in short sentences. Explaining, patiently, that she was controlling. That she wanted to run him out of his own son’s life.
I asked him, gently, what happens in his body when he reads her long, precise texts about the schedule. He stared at the floor for a long time. Then he said, quiet: “My chest goes freezing cold. My throat closes up. I feel like a little kid who’s failed a test. I feel like I’m about to be told I’m not a real father.”
Her face changed. I watched it happen. The sharp, prosecutorial posture softened. Something in her chest dropped an inch. She had spent two years seeing a stonewalling narcissist, and for the first time she saw a scared boy inside a man she used to love.
I turned to her. Asked what happens in her body when he brings their son back late. She said: “I feel completely alone. Like I’m the only one holding this child, and no one is coming. Like it’s all on me and if I put it down for a second everything falls apart.”
Two suffering nervous systems. One story between them, told from two ends of the same rope.
They did not become friends. They did not remarry. But something shifted in the driveway. The stomachaches stopped.
That is the actual work of co-parenting boundaries. Not a better app. A dropped defense on both sides, for the sake of the small body watching.
The Sovereign Us After the Marriage Ends
I know a version of this is going to be hard to hear. Some of you are co-parenting with someone who is genuinely dangerous, genuinely dishonest, genuinely refusing any accountability. For you, walls are safety, and I am not going to argue with your walls. Please keep them.
But most co-parents I sit with are not in that category. Most are two decent, wounded people who could not make a marriage work and are now trying to do the second-hardest thing there is: raise a child together from two houses.
For you, the work is not to become a fortress. The work is to build what I call, in my clinical writing, a secure functioning unit that survives the end of the marriage in a new form. A container that holds your child even when the marriage cannot hold you.
That container is not built with lawyers. It is built moment by moment, one regulated response at a time. It is built when you notice your body is on fire and you wait an hour before replying. It is built when you catch yourself building the Story of Other and gently, without shaming yourself, turn the flashlight back around. It is built when you can, on a good day, imagine your ex not as the villain of your life but as a wobbly parent trying not to fail the same child you are trying not to fail.
This is proof of work. And it is the only real co-parenting boundary that holds.
This is not a you problem or a them problem
“Round and round they go. Escalating judgments. Reaffirming worst fears. Two people throwing emotional boomerangs, doing exactly what makes logical sense to survive their own pain, only to gut their partner and ensure their own continued suffering. The way you try to get out of feeling hurt and threatened usually hurts and threatens your partner.”
“The fight is never about the content. It is always about the bond.”
Figs O’Sullivan, LMFT
Common Questions
How do I set co-parenting boundaries with a high-conflict ex without escalating things?
Start by getting your own nervous system out of threat before you communicate. Draft the message, wait an hour, read it back. Ask if it is a boundary about the child or a wall about winning. Keep the content minimal, specific, and about logistics. Do not defend, do not explain past what is necessary. Regulated brevity is your friend. If your body is on fire, the message will leak that heat no matter how polite the words are.
What if my ex keeps violating the boundaries we agreed on?
Chronic violation is almost always a shame signal, not a power grab. The boundary is landing on their body as evidence they are a failing parent, and their protector part is pushing back to relieve that unbearable feeling. This does not make it okay. It means the fix is rarely a tighter rule. Where you can, name the underlying concern once, in writing, in a regulated moment. Then hold the agreement without emotional escalation. If violations continue and affect the child, that is when you escalate through legal channels, not through text warfare.
Can you have healthy co-parenting boundaries and still be friendly with your ex?
Yes, and honestly, some version of this is what serves the child best. Friendly does not mean re-entangled. It means two adults who can be in the same room at a school play without the air going toxic. The key is that your friendliness comes from a genuinely regulated place, not from a fawn response or a hope that you might reconcile. If being friendly requires you to abandon yourself, it is not friendly, it is a wall wearing a smile.
How do I stop my ex from talking badly about me to our kids?
You cannot control what happens in the other house. You can control what your child experiences in yours. Do not counter-badmouth, even when it is deserved. Your child’s nervous system is reading both parents constantly, and speaking ill of the other parent lands in your child’s body as a threat, not a vindication. Instead, be the steady ground. Kids figure out the truth over time, and they remember which parent held their nervous system without weaponizing the other one.
What does emotionally healthy co-parenting actually look like day to day?
It looks less dramatic than you’d expect. Handoffs that don’t feel like hostage exchanges. Texts that get answered within a reasonable window without ten drafts. School events where both parents can sit in the same row. Decisions about doctors and schools made through actual conversation, not through lawyer-mediated warfare. Nobody is friends necessarily. But nobody’s body is on high alert either. The child in the middle can exhale.
Do not just close the tab on this.
Bring what surfaced here into a real conversation. Figlet coaches you through it, grounded in Figs O’Sullivan’s work, LMFT. Free to start.
The custody schedule is not the fight. The fight is whether you can put the flashlight down long enough to notice your own body burning, and choose the child in the middle instead of the case in your head. That’s the work. It doesn’t end. Start tonight.
Keep Reading
Every couple has a pattern they cannot see. Find yours.
In love, each of you is a Relentless or a Reluctant, which makes you one of three kinds of couple: Relentless and Reluctant, two Relentless, or two Reluctant. The free quiz reveals your creatures and the cycle they fall into together. About three minutes.
No signup needed to start.
The Relentless
The Reluctant
