How to Rewire Your Brain During and After Divorce: A Neuroscientist Explains

What's Actually Happening in Your Brain During Divorce—and How to Fix It

You're not imagining it. The brain fog, the inability to focus, the way you keep replaying painful conversations on an endless loop—there's actual neuroscience behind what you're experiencing during divorce.

I sat down with neuroscientist Dr. Nicole A. Tetreault to understand exactly what's happening in our brains during one of life's most stressful transitions. What she shared wasn't just fascinating—it was practical, actionable, and honestly, a relief to hear.

If you've felt like you're "losing it" during your divorce, this conversation will help you understand why—and more importantly, what you can do about it.

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Your Brain on Divorce: What's Really Happening

Dr. Nicole didn't sugarcoat it: divorce aligns with trauma. And when we experience trauma, our emotional capabilities get thrown out of the normal range.

Here's what's actually going on:

• Your stress hormones are maxed out. Cortisol and adrenaline are running at their highest levels. When you stay in that constant fight-or-flight state, it doesn't just affect your brain—it affects your entire body.

  
  

• You can't access your frontal cortex properly. That's the part of your brain responsible for executive decision-making, planning, and emotional regulation. So when you need it most—to make major financial decisions, negotiate custody arrangements, handle legal paperwork—that's exactly when it's hardest to access clear thinking.

  
  

• Everything becomes emotionally charged. Money becomes emotional. That book you bought together in college suddenly becomes a point of contention. Things that shouldn't matter suddenly feel like they matter enormously. That's not you being irrational—that's trauma response.

  
  

• The inflammatory process creates a cycle. Brain fog, headaches, stomach issues, changes in your eating patterns—it's all connected. Dr. Nicole explained the gut-brain connection: we have what amounts to a "cat-sized brain" in our gut. That pit in your stomach you feel?

That's directly affecting your ability to think clearly.

The Negative Thought Loop—And How to Break It

One of the most important things Dr. Nicole explained is what she calls "the inner critic" or "the monster"—those negative thought patterns that feel impossible to escape.

Here's the science: we're all wired with a negative thought bias. When you're feeling down or going through a tough time, that bias gets amplified. You're not weak for experiencing this. Your brain is literally doing what it's programmed to do.

But here's the critical part: 90-95% of our worries never come true. They're not factually based.

So when you're lying awake at 3 AM convinced that you're going to lose everything, that your financial future is destroyed, that you'll never recover—pause. Check the facts. What evidence do you actually have that this catastrophic outcome will happen?

The Power of the Pause

Dr. Nicole's advice was deceptively simple: When you're caught in a negative loop, pause and take a really deep breath.

Most of the time when we're experiencing these cyclical thoughts, our brain and body are running patterns we're used to. When we pause and breathe, we can get present to where we actually are—which is usually safe in that moment.

The key is recognizing that rumination is fear-based. You're running these cycles because some part of you thinks you're not safe. You're anticipating future hurt, future worry, future loss.

But if you're responding out of fear at every single moment, you're not going to have the groundedness to actually advocate for yourself appropriately.

Stress Response Patterns: Which One Are You?

Dr. Nicole explained that we each have natural patterns for how we react to stress, developed from how we were raised. These patterns fall into four to five main categories:

• Fight or Flight: You get that energy out. You move. You feel strong and powerful.

• Freeze or Flop: You shut down. You're on your back. This is where the brain fog really lives.

• Fawn: You people-please and try to smooth things over.

Understanding your pattern helps you recognize when you're in it—and gives you the power to choose a different response.

Neuroplasticity: You Can Actually Rewire Your Brain

Here's the good news that Dr. Nicole emphasized: your brain is plastic. You have the ability to write new stories. You have the ability to change the way you think about things.

This isn't just positive thinking—this is neuroscience. When you're going through divorce, you experience something called post-traumatic growth. This process actually allows for new wiring, new neuroplasticity, and new patterns to be developed.

But it takes intentional practice.

Training Your Brain to Stop Reacting to Your Ex

This came up specifically around co-parenting with a difficult ex-spouse. When you've been in a pattern with someone for years—decades even—those neural pathways are deeply worn.

Dr. Nicole's advice: Focus on what matters most. When you can come back to the story that the most important thing is your relationship with your child and that your child's needs come above everything else, you can actually make that a motivation to not fall into reactionary patterns.

It doesn't mean your ex won't still show up an hour and a half late. But instead of screaming and blowing up (your old pattern), you can say, "Not cool," and move on. You work through that rewiring where the emotional reactivity doesn't happen.

Each time you rewire that new pattern, you create a new groove in your brain. Again and again and again. Until eventually, they're late and you're like, "Oh yeah, this is normal," and it doesn't phase you anymore.

The Midlife Divorce Awakening

One of the most powerful parts of our conversation was about why so many divorces happen in midlife—and why that's not necessarily a bad thing.

Dr. Nicole explained that midlife brings an awakening. Kids move away (or you never had kids). You realize you have half your life left to live and there are things you want to get done. You need a partner willing to grow with you, to diverge and come back in this flowing pattern.

When you have a partner who's not on board with that growth, waking up every day not wanting to be there—that's not a life worth living.

Divorce at midlife isn't failure. It's often a catalyst for becoming who you're actually meant to be.

Want more about this subject? → Read: Midlife Divorce as an Awakening Guide

Avoiding Toxic Relationship Patterns When Dating Again

Dr. Nicole had a fascinating perspective on why we often pick the partners we do: we marry someone because they fit into patterns we're used to from our childhood. We're working through clearing those patterns.

The real work before jumping into a new relationship is understanding what those initial patterns and triggers are. Otherwise, you'll just repeat them with someone new.

This takes self-awareness, introspection, and often professional support—whether that's therapy, coaching, or both.

One Thing You Can Do TODAY to Start Healing Your Brain

I asked Dr. Nicole for one concrete action someone could take today to start rewiring their brain. Her answer was beautifully simple:

Write down your intention.

That's it. Write down the intention of what you want that new pattern to be.

Examples:

• "I intend to not blow up every time my ex is late."

• "I intend to respond with calm when my ex tries to provoke me."

• "I intend to focus on gratitude each morning."

  
  

And here's the important part: when you inevitably mess up (because you will—you're human), you respond with compassion. "Ah, I blew up this time. I'm not perfect. I'm a work in progress."

The intention keeps you anchored. It reminds you what you're working toward. And each time you honor that intention, you're literally creating new neural pathways.

Start a Gratitude Practice

Dr. Nicole also emphasized gratitude as a powerful rewiring tool. It doesn't have to be complicated:

• I woke up today.

• I have water.

• I have food.

• I'm working through this hard thing with awareness.

If you want structure around this, I created a free gratitude journal specifically for people going through divorce: → Download: Free Gratitude Journal

The Role of Support in Healing Your Brain

One of the most important things Dr. Nicole said: We need people.

Yes, we can learn to regulate our nervous system. We can breathe and find our center. But in everyday life, especially during crisis, we need other people.

Have a trusted friend you can call when you're triggered. Someone who can say, "Hey, what you're thinking isn't reality. Let me help you see this more clearly."

This is also where working with a divorce coach or therapist becomes critical. You're not going to talk through this once and be done. Healing isn't a one-and-done proposition. We humans do well by talking things out over and over and over again.

Give yourself permission to need support. Give yourself permission to process this as many times as you need to.

Compassion, Compassion, Compassion

Throughout our entire conversation, Dr. Nicole kept coming back to one word: compassion.

Have compassion for yourself that this awakening has come. It's a hard, rude awakening—and you're not alone.

Have compassion for yourself when you fall back into old patterns.

Have compassion for yourself when your brain feels foggy and you can't think straight.

Have compassion for yourself as you navigate this impossible situation of making major life decisions while your brain is experiencing trauma.

The kindness you'd extend to a friend going through this? Extend that to yourself. YOU deserve it.

Your Brain Can Heal—And So Can You

The most hopeful message from my conversation with Dr. Nicole is this: your brain has the capacity to heal, to rewire, to create new patterns.

You're not stuck with the negative loops. You're not stuck with the reactivity. You're not stuck repeating the same relationship patterns.

It takes awareness. It takes intention. It takes practice and support. But it's possible.

And the work you do now to understand your patterns, to rewire your responses, to heal your brain—that's not just about getting through divorce. That's about creating a foundation for the rest of your life.

Watch the Full Conversation

If you haven't watched the full video yet, I really encourage you to. Dr. Nicole goes much deeper into the neuroscience, and hearing her explain these concepts with such clarity and compassion is truly valuable -- during divorce and beyond!