Why You Stay in Toxic Love: The Hormonal Science of Codependency
- Updated: April 16, 2025
Ever wonder why you know someone is bad for you—but you still can’t walk away?
You’re not weak or clueless. You’re likely just hijacked by your hormones.
Hormones aren’t just for moods or metabolism. They quietly run the show behind your cravings, your fears, and yes—your relationships. Especially the ones that hurt.
As a healing and leadership coach, I’m obsessed with this stuff. Because when someone says, “I don’t know why I keep going back,” I want to scream, “Actually, I do—and it’s biochemical.”
This article breaks down the science behind those stuck patterns—how neurotransmitters and hormones shape your thinking, your body, and your ability to leave pain-filled love behind.
Let’s get into it.
Your Brain’s Messaging System: What Neurotransmitters Are—and Why They Matter
Ever flinched before touching a hot stove—or felt your stomach drop before a hard conversation? That’s not magic. That’s neurotransmitters at work.
These little chemical messengers travel fast. Like really fast. They zip between nerve cells, helping your brain and body talk to each other in real time. Emotions. Impulses. Reactions. All of it.
Now, here’s where it gets interesting: neurotransmitters aren’t the same as hormones, but they often work together. And when they do? They can totally hijack your sense of logic.
Which brings us here…
Fast Signals, Deep Patterns: How Your Brain Reacts Before You Can Think
Imagine your nervous system as a messaging grid. When you get startled, signals race at up to 270 mph to help you react. Pain signals are slower, more like stop-and-go traffic. But both types shape how you respond—emotionally and physically.
In the heat of a relationship? These same lightning-fast signals can override logic.
So now you know neurotransmitters are the quick messengers. But they’re not acting alone.
There’s another group of chemicals that play the long game—and they can mess with your body, your brain, and your boundaries. I’m talking about hormones.
Hormones vs. Neurotransmitters: Same Chemistry, Different Chaos
It’s easy to confuse the two—both affect how you feel and act. But they serve different purposes:
| What It Does | What It Doesn’t Do | |
|---|---|---|
| Neurotransmitters | Send electrical signals between brain cells. | Can’t travel through blood or regulate long-term body processes. |
| Hormones | Control body functions (like digestion, stress, and growth). | Can’t deliver fast, targeted reactions like neurotransmitters. |
They often team up—especially during emotional events. And when that happens? You may act in ways that make no sense logically.
And here’s where it really messes with you:
When neurotransmitters and hormones team up during emotional moments—especially in relationships—they don’t just nudge your behavior. They take the wheel.
Suddenly, you’re not just reacting to what’s happening—you’re stuck in a cycle your body thinks is love… even if it’s chaos.
The Toxic Rush: Why Chaos Feels Like Chemistry
Think of a toxic relationship like a rollercoaster: thrilling highs, stomach-dropping lows—and the worst part? You start craving the ride.
You might know the relationship is bad. But your body, flooded with cortisol and norepinephrine, gets hooked on the adrenaline. It’s not love. It’s survival-mode on a loop.
I had a client once who said, “I don’t even like him—but when he texts, my heart still jumps.”
That wasn’t desire. That was a stress response. Her body had learned to confuse danger with chemistry.
Cortisol Overload: When Stress Becomes an Addiction
One client told me she hated the fights but loved the makeup sex. It wasn’t just the drama. It was the chemical payoff.
Cortisol helps your body respond to danger. But when it stays high for too long, it backfires—causing anxiety, brain fog, and heart problems.
Still, your brain learns to crave it. Cortisol becomes the familiar storm.
In the next section, we’ll discuss specific neurotransmitters that act as hormones, making us do the most inexplicable things in the name of “love,” or rather, fear of being abandoned and rejected.
Love, Lust, and Lies: How Hormones Hijack Your Judgment
Here’s where the bond deepens. Hormones like oxytocin, dopamine, serotonin, and endorphins kick in. Each one rewards the relationship—even if it’s dysfunctional.
Let’s break it down:
Oxytocin: The Love Hormone That Doesn’t Care If He’s Toxic
Oxytocin is often called the “love hormone.” It’s the chemical behind bonding—the one that kicks in during sex, cuddling, or late-night confessions that feel deeper than they are. It’s what makes you feel close, even when every red flag is screaming, run.
But here’s the problem:
Oxytocin doesn’t care if he respects you.
It doesn’t care if he lies, ghosts, or gaslights.
It just cares that he’s near.
Dr. Pat Allen, a longtime family therapist, once said:
“As soon as a man puts his penis into your mouth, anus, or vagina, you’re hooked.”
Crude? Yes.
Wrong? Not at all.
Looking back on my single years, I can see how many situations I stayed in that should’ve ended on day two. No emotional connection. No communication. Just physical intimacy way too early—and a body that confused closeness with commitment.
Why You Can’t Just “Get Over Him”: The Illusion of Bonding
Ever dated a guy for two months, then spent the next two years missing him?
That’s not heartbreak. That’s oxytocin doing its thing.
When there’s any form of penetration—yes, vaginal, oral, or anal—your body releases oxytocin. And that bond? It can biologically linger for up to three years.
Here’s why: your body assumes you’re trying to make a baby. And nature wants that baby to survive.
It takes around three years for a child’s mirror neurons to fully develop. So your brain’s wiring tries to keep the “family” together—whether or not the guy’s actually safe, stable, or sane.
You’re not in love. You’re in a trance.
A hormonal loop that says, Stay close. This is survival.
I can’t tell you how many “entanglements” I stayed in—not because I believed in the relationship, but because my body had already made the bond.
Dopamine and Denial: How Your Brain Prioritizes Pleasure Over Peace
Dopamine is your brain’s “feel-good” chemical. It spikes when you anticipate pleasure—and that’s where the trouble begins.
In toxic relationships, your brain becomes obsessed with the good moments. The laughs. The sex. That one weekend he actually showed up for you.
You ignore the cheating, the gaslighting, the disrespect—because dopamine reinforces the fantasy. You’re not just stuck in the past. You’re stuck in a reward loop.
This is the neuroscience behind the “on-again, off-again” mess. It’s not weakness. It’s wiring.
Obsessed and Unsettled: When Low Serotonin Keeps You Clinging
Serotonin helps regulate mood and obsessive behavior. When it’s low, you can’t stop spinning.
Ever reread old texts? Replayed arguments in your head? Checked his Instagram even though you swore you wouldn’t?
That’s not you being dramatic. That’s serotonin depletion. Your brain is trying to stabilize itself—but it’s doing it by obsessing over the person who destabilized you.
The best example? Glenn Close in Fatal Attraction.
Obsessed. Frantic. Boiling rabbits.
You might not go that far, but you feel that intense pull. That’s not love. That’s neurochemistry gone rogue.
Understanding Endorphins: Numbing Pain and Complicating Healing
Endorphins are your body’s natural painkillers. They get released during physical or emotional stress to help you survive.
But here’s where it gets twisted: sometimes, those endorphins actually make you feel good while you’re being hurt.
That’s why victims in abusive relationships may describe feeling high after an intense fight—or oddly calm in the middle of chaos.
I once heard a story of a woman who returned to her husband after he hospitalized her. She said, “He’s just stressed from work.”
She wasn’t just rationalizing. Her body was flooded with endorphins, numbing the trauma and creating a bizarre sense of loyalty.
The brain was trying to protect her.
But it was also keeping her stuck.
Up next: how to heal when your body is still hooked.
(And yes, you can unhook. Even from this.)
Rebalancing After the Storm: How to Heal Your Hormonal Hangover
Getting out of a painful relationship isn’t the finish line—it’s the detox.
When your body’s been running on stress hormones, adrenaline spikes, and chemical bonding for months (or years), you don’t just “move on.” You have to reset your system.
Here’s how to start clearing out the emotional residue and get your body and brain back to baseline:
1. Find Creative Outlets
You don’t need to be an artist—you just need a release valve.
Paint. Journal. Make playlists. Scribble messy poetry. Learn the guitar. Creativity helps your nervous system shift out of survival mode. It lets your brain feel pleasure that isn’t tangled in conflict or chaos.
2. Cut the Drama
Your body can’t heal if your screen time is full of screaming matches, murder docs, or messy reality TV.
I’m not saying go full monk—but know this: watching drama keeps your system wired for it. Your brain starts thinking chaos is normal.
Swap some of that stimulation for calm: nature shows, silence, music that soothes instead of spikes.
3. Eat Like You’re Rebuilding Something
Food is mood. What you eat literally becomes your neurotransmitters.
So no, it’s not “just a snack.” It’s your recovery fuel. Slow down. Choose real food. Pay attention to how it makes you feel.
Your brain can’t stabilize if your blood sugar is crashing every two hours.
4. Get Help. Real Help.
You don’t have to figure this out alone. You’re not weak for needing support—you’re wise.
Whether it’s a therapist, coach, or support group, having someone help you process the emotional weight can make all the difference. Especially someone trained in trauma or relationship dynamics.
Each of these steps isn’t just self-care—it’s chemical recovery.
Give yourself grace. Your brain is rewiring. Your body is learning what calm feels like again. That’s the work.
Up next: the final thoughts you didn’t know you needed.
Final Thoughts
If you’ve made it this far, then some part of you already knows—this isn’t just emotional.
It’s biological. Psychological. Neurological.
This isn’t about repeating affirmations or blasting empowerment playlists.
It’s about undoing chemical bonds that were wired through trauma, loneliness, or survival.
If you’ve felt stuck…if you’ve gone back to someone who hurt you…if you’ve confused chaos with chemistry—you’re not weak. You’re responding to years of internal patterning.
But patterns can be broken.
I hope this article gave you more than insight. I hope it gave you permission.
Permission to:
Leave—emotionally, then physically, and finally, spiritually.
Get help—ask someone to support you in breaking the habits that hurt you.
Stop waiting for them to change—no more holding onto hope that was never really there.
You don’t have to do it alone. And you don’t have to keep pretending it’s not that bad.
Have you been through a painful relationship?
I’d love to hear your story—because your truth might help someone else feel less alone.
👉 Share your experience here.
If you want support:
- 🎯 Learn how I support clients in breaking patterns and building something healthier—emotionally, mentally, and relationally.
- 🎙️ Or tune in to my podcast for raw, real conversations on trauma, healing, and what it actually means to grow.
You can get free. You can feel whole.
And you don’t have to wait for the perfect moment.
Start with the next decision you make.
