Psychology says people who took years to acknowledge an unhappy marriage aren't in denial - they're doing the constant cognitive arithmetic of staying versus leaving, and the calculation keeps changing depending on the day

A couple I knew in Melbourne stayed married for eleven years past the point where anyone close to them would have called it a good marriage. They weren't dramatic about it. No screaming matches at barbecues, no public unraveling. He coached their son's cricket team. She ran a consulting business from a home office that doubled as a guest room she increasingly slept in. From the outside, it looked like a functioning life. From the inside, both of them were doing math every single day. Staying versus leaving. The answer changed depending on the week.

I think about them whenever someone says, "How did they not see it sooner?" Because they did see it. They saw it constantly. They just kept arriving at different answers. Psychology backs this up. People who take years to acknowledge an unhappy marriage aren't failing to see the truth. They're running a constant internal calculation, weighing what they'd lose against what they might gain. The answer keeps shifting depending on the day, the week, and what happened at the dinner table last night.

The Stay-or-Leave Equation Is Never Static

Psychologist Dr. Samantha Joel, whose research at Western University focuses on how people make decisions about romantic relationships, conducted a landmark study that uncovered something most outsiders never consider: people deliberating whether to end a relationship hold simultaneous reasons for wanting to stay and wanting to leave.

Her study, published in Social Psychological and Personality Science, identified 27 distinct reasons people want to stay in a relationship and 23 reasons they want to leave. The critical finding was that about half of the participants endorsed reasons from both lists at the same time. They weren't confused. They were ambivalent. And that ambivalence wasn't a bug in their thinking. It was an accurate reflection of how complicated the decision actually is.

As Joel put it in a press release from the University of Utah: people felt genuinely torn. From the outside, someone might look at a troubled relationship and think the answer is obvious, but from the inside, the calculation is agonizing. It only gets harder the longer you've been in it.

Married People and Dating People Do the Math Differently

One of the most revealing details from Joel's research was the difference between how dating people and married people weighed their reasons to stay. People in dating relationships cited positive reasons: personality traits they liked, emotional closeness, genuine enjoyment. Married people leaned more heavily on what psychologists call constraint reasons. Shared investment. Family obligations. Financial entanglement. Fear of the unknown.

That's not love talking. That's logistics. It doesn't mean the love is gone. It means the equation has more variables now. Children. A mortgage. The in-laws. A shared circle of friends who will have to pick sides. A version of yourself that's been "married" for so long you're not sure who you are without it.

I've seen this play out in Saigon, too, among expat couples who moved abroad together and suddenly realized the marriage was the only familiar thing left. Walking away doesn't just mean divorce. It means dismantling the entire architecture of a life built in a foreign country.

This is why the research on stay/leave ambivalence, published in the European Journal of Social Psychology, found that ambivalent individuals don't just feel conflicted in a general sense. Their commitment levels actually fluctuate from day to day. On good days, they feel more motivated to stay. On bad days, they lean toward leaving. The calculation never stops. It just keeps recalibrating.

Ambivalence Isn't Weakness. It's the Brain Doing Its Job.

There's a cultural assumption that clarity is a sign of strength and ambivalence is a sign of weakness. We praise people who "just know" and side-eye the ones who can't make up their minds. But that framing ignores what psychologists have been documenting for years: ambivalence in close relationships is not only common, it's often rational.

A study discussed in Psychology Today, based on data from the Iowa Midlife Transition Project, found that feelings of marital ambivalence predicted divorce up to seven years later. But it also found that ambivalence correlated with lower satisfaction even in couples who stayed together. The ambivalence wasn't a phase. It was a signal. Ignoring it didn't make it go away. It just made everything quieter and more corrosive.

The person sitting across from you at breakfast who seems fine? They may be running the numbers again. Weighing last night's argument against the kids' soccer schedule. Balancing the resentment they felt on Tuesday against the moment of connection they felt on Thursday. It's not denial. It's an exhausting, invisible arithmetic that reshapes itself with every interaction.

The Sunk Cost Trap Makes It Worse

On top of the ambivalence, there's another force holding people in place: the sunk cost fallacy. This is the well-documented cognitive bias where people continue investing in something — a project, a business, a relationship — simply because they've already invested so much.

In the context of marriage, it sounds like: "We've been together fifteen years. I can't just throw that away." The years, the shared history, the emotional labour. All of it starts to feel like proof that you should stay, even when the future offers diminishing returns. A study from the University of Minho, published in Current Psychology, confirmed this experimentally: people who had invested more time, effort, or money into a hypothetical relationship were more likely to say they'd stick it out, even when told the relationship was making them unhappy. Those who imagined a ten-year relationship stuck around an average of 294 days longer than those who imagined a one-year relationship.

The math isn't just emotional. It's cognitive. Your brain is literally weighting past investment as evidence that future investment is worthwhile, even when it isn't.

Then There's Cognitive Dissonance

Here's where it gets really tangled. When someone believes they're in a good marriage but feels unhappy, the conflict between those two things creates what psychologists call cognitive dissonance. A deep psychological discomfort that the brain will do almost anything to resolve.

And the easiest way to resolve it? Convince yourself you're not that unhappy. Downplay the bad nights. Inflate the good ones. Tell yourself that all marriages are hard. Compare your situation to someone else's and decide yours isn't so bad. This isn't stupidity. It's a survival mechanism. The brain prefers consistency over accuracy, and rewriting the story is often easier than blowing up your life.

This is where I think we need to be honest about something. At a certain point, the constant recalculation stops being rational and starts becoming its own form of paralysis. I understand the complexity. I've watched people I care about live inside it for years. But there's a difference between genuine ambivalence and using the complexity of the decision as a reason to never make one. The arithmetic can become a hiding place. Not always. But sometimes.

The Calculation Finally Tips

So what changes? Usually, it's not one dramatic moment. Research from Joel and others suggests that humans carry a natural progression bias in relationships. A tendency to keep moving forward rather than pull the plug. That's why people often need the scales to tip significantly and consistently before they act. Not just one bad day. Not just one fight. A pattern that finally becomes impossible to rewrite.

Sometimes it's a moment of contrast. A glimpse of what peace might feel like. Sometimes it's their child saying something that forces them to see the relationship through different eyes. Sometimes it's simply exhaustion. The arithmetic has been running for so long that the person no longer has the energy to keep balancing the equation.

But it wasn't denial that kept them there. It was the weight of a decision that touched every corner of their life. Financial, social, emotional, logistical, existential. It was the fact that on some days, the reasons to stay genuinely outnumbered the reasons to go. And on other days, they didn't.

What the Research Wants You to Understand

If you've ever watched someone stay in an unhappy marriage and wondered what they were thinking, the answer is: everything. They were thinking about everything, all the time, and the answer kept changing.

The research is clear: relational ambivalence is not a failure of insight. It's a feature of being a person who built something real and now has to decide, day by day, whether to keep building or walk away. That decision doesn't happen in one moment. It happens in thousands of them. Quietly, at the kitchen counter and in the car on the way to work and at 2 a.m. when the house is silent.

And here's where I'll take a clear position: society's impatience with these people is not justified. The friends who say "just leave," the family members who roll their eyes, the culture that treats decisive action as inherently superior to careful deliberation. They're wrong. Not because staying is always the right call. Sometimes the calculation becomes avoidance, and I've said as much. But the expectation that someone should blow up a life on a timeline that makes other people comfortable is arrogant. The word "just" has never once applied to the dismantling of an entire life, and anyone who uses it hasn't done the math themselves.