Why It's So Hard to Leave a Relationship That Isn't Working

As a clinical psychologist, I've noticed something interesting. People rarely come to therapy saying, "I know I need to leave my relationship." Instead, they spend months, or sometimes years, talking about what's happening inside the relationship. They describe feeling lonely despite having a partner, walking on eggshells, or replaying arguments in their heads. They tell me they feel anxious, unheard, or emotionally exhausted. Then, almost in the same breath, they'll say, "But they're actually a really good person," or "Things weren't always like this."

The following week they come back with another story. Another painful interaction. Another apology. Another promise that things will be different. And the relationship continues. In my experience, this is one of the most confusing experiences people have, not because they don't recognize the problems, but because recognizing them doesn't seem to change what they do next.

Recently, millions of people watched this exact dynamic unfold on Love Island USA with Melanie and Sincere (whatttt, psychologists watch reality TV?!). Week after week, viewers watched Melanie describe how hurt, confused, and emotionally exhausted she felt after interactions with Sincere and him saying one thing and doing another. She confronted him, cried, questioned whether she could trust him, and repeatedly expressed that she deserved better. Yet despite all of this, she continued choosing the relationship. Social media was flooded with the same question: "Why can't she see him for who he is" and "why doesn't she just move on?"

Watching from the outside, the answer often seems obvious. But as psychologists, we know the more interesting question isn't why don't people leave? It's what keeps intelligent, capable people emotionally invested in relationships that consistently leave them hurting? The answer has far less to do with weakness than most people realize.

One of the biggest misconceptions about unhealthy relationships is that people stay because they don't recognize the problems. In my experience, that's rarely the case. Most people have tremendous insight. They know they're unhappy. They know their needs aren't being met. They know they're having the same conversations without meaningful change. Insight is often present long before change occurs. The difficult part isn't recognizing the problem; it's acting on that recognition.

Part of the answer lies in a concept from social psychology (one of my favourite branches of psychology) called cognitive dissonance. Cognitive dissonance refers to the discomfort we experience when two beliefs don't fit together. Imagine holding these two thoughts at the same time: I'm a thoughtful person who makes good decisions, and I've invested years in a relationship that consistently hurts me. Those ideas create psychological tension, and our brains naturally try to reduce it.

One (obvious) way to reduce that tension would be to leave the relationship. But another, often less frightening option, is to change the story we tell ourselves. We begin thinking, They're under a lot of stress right now, or Relationships take work, or Things have been getting better lately. Sometimes these explanations are completely accurate. Other times, they help us make staying feel more consistent with the belief that we've made good choices. This isn't about being irrational. It's about our minds trying to create consistency.

Once we've invested in a relationship, another process often takes over: confirmation bias. Confirmation bias is our tendency to notice information that supports what we already believe while giving less weight to information that contradicts it. We find ourselves focusing on the heartfelt apology, the wonderful weekend together, or the version of our partner we know they're capable of being. Those moments are real, but they can begin to outweigh months of feeling dismissed, anxious, or emotionally alone because our brains are searching for evidence that staying is still the right decision.

Social psychologists have another explanation for why leaving becomes harder over time: the investment model. Research has shown that commitment isn't determined by love alone. It's also shaped by everything we've invested in the relationship, including our time, emotional energy, shared memories, mutual friends, living arrangements, children, and plans for the future. The more we've built a life around someone, the more difficult it becomes to imagine walking away, even when the relationship itself is no longer meeting our needs.

The investment model is closely related to what's known as the sunk cost effect. Imagine spending thousands of dollars renovating your home before discovering major structural problems. Most people don't immediately stop spending. Instead, they think, I've already put so much into this. I can't quit now. Relationships often work in exactly the same way. After a substantial time together, many people tell themselves, I don't want all of this to have been for nothing. But the difficult reality is that past investments can't be recovered by making future ones. Staying another five years doesn't automatically make the first five worthwhile.

Hope also plays an incredibly powerful role. Relationships that are difficult to leave are rarely painful all the time. There are moments of warmth, affection, laughter, and genuine connection. There are apologies that feel sincere and periods where things really do improve. Those moments keep hope alive. Many people aren't staying because they're happy with the relationship they have; they're staying because they're deeply attached to the relationship they believe is still possible.

Ironically, I often see this struggle in highly intelligent and psychologically minded people. They're skilled at seeing nuance. They understand how childhood experiences, trauma, attachment, stress, or mental health can shape behaviour. That empathy is a strength, but it can also make it easier to tolerate behaviour that repeatedly causes them pain. Understanding why someone behaves the way they do doesn't mean you have to continue accepting behaviour that doesn't align with your values or goals. Compassion and boundaries can exist at the same time.

When clients ask me whether they should stay or leave, I rarely answer the question directly. Instead, I ask them something else. If nothing changed from today onward, if your partner remained exactly as they are now for the next five years, would you choose this relationship?

It's a simple question, but it often shifts the conversation. Many people realize they've been making decisions based on potential rather than reality. They're not evaluating the relationship they're actually in. They're evaluating the one they hope they'll eventually have.

If you've found yourself talking about the same relationship problems over and over while feeling unable to leave, it doesn't necessarily mean you're weak, dependent, or lacking insight. More often, it means you're human. Our minds are wired to reduce internal conflict, justify past investments, hold onto hope, and avoid painful uncertainty. Understanding cognitive dissonance, confirmation bias, and the investment model won't make difficult decisions easy, but it can help explain why knowing something isn't working doesn't automatically give us the ability to walk away.

Perhaps the better question isn't, "Why do I keep staying?" Instead, ask yourself this:

If I met this person today, knowing everything I know now, would I choose this relationship again?

For many people, that's the question that begins to cut through hope, history, and habit. While the answer isn't always easy to hear, it often marks the beginning of meaningful change.

Dr. Danielle Kofler, C.Psych.

Clinical Psychologist and Clinic Director of One Psychology Clinic

Dr. Danielle Kofler