I know I need to leave but I can't

I have encountered countless instances of people staying in relationships and withstanding profoundly unhealthy dynamics - for years, sometimes decades. As human beings we can be remarkably adaptive and resilient. Both to our benefit and, at times, to our detriment. This article isn't about telling you what to do, but rather helping you understand why leaving might feel so hard - because that understanding is often the first step towards finding your own answer.

When the relationship starts to break down

Relationship deterioration rarely happens overnight. It compounds. Resentment builds slowly, criticism becomes the default register, and corrosive contempt enters the dynamic. Psychologist and researcher John Gottman, who spent decades studying couples, identified what he called the Four Horsemen: criticism, contempt, defensiveness and stonewalling. His research found that contempt in particular - the sense that one partner regards the other with disdain, superiority or mockery - is the single strongest predictor of relationship breakdown.

When arguments happen repeatedly without resolution, without repair, without either person feeling heard or acknowledged, the damage accumulates. Trust erodes. Emotional safety disappears. The relationship begins to feel like something to be managed rather than a source of connection.

Sometimes the signs are overt - explosive arguments, threats to leave, unpredictability, behaviour that frightens. Sometimes they are quieter. Passive aggression. Silence. Emotional withdrawal. A refusal to compromise. On the surface, a shared home, a functional life, families spending time together. Something that looks intact from the outside and feels hollowed out from within.

In more serious cases, the dynamic can tip into coercive control - the slow erosion of confidence and self-worth through criticism, shame, and the insidious suggestion that no one else would want you, that you would not survive alone. This is a particular kind of harm and one worth naming, because it works precisely by making leaving feel impossible before you have even considered it.

Why the attachment system keeps you there

Understanding why leaving feels so hard requires understanding what the attachment system does under these conditions - because it does not simply switch off when a relationship becomes painful.

British psychiatrist and psychoanalyst John Bowlby, whose work on attachment theory transformed how we understand human connection, showed that the need for proximity to an attachment figure is one of the most fundamental drives we have. When that bond is threatened - even by the attachment figure themselves - the system activates. It reaches for closeness, for repair, for the moments of warmth that briefly return and temporarily restore hope.

This is why the cyclical nature of difficult relationships can be so difficult to exit. The arguments, the tension, the withdrawal - and then the rare period of calm, of ease, of the person you fell in love with briefly reappearing. The nervous system responds to those moments with relief and hope. It updates, however briefly, towards staying. The attachment system is not weighing up the relationship rationally. It is doing what it was designed to do - seeking proximity to the person it is bonded to, regardless of whether that person is currently a source of safety or harm. This is not weakness, but biology.

The weight of a shared life

Beyond the attachment piece, there is the sheer practical and emotional weight of what leaving would mean. A shared home. Shared finances. Perhaps one partner reliant on the other's income. Intertwined families and friendships built over years. Children. The commitment of marriage. Cultural or religious expectations around staying together. Societal pressure to make it work.

And the emotional weight - the memory of when things were better, the investment of years, the shared future that was being built and would have to be grieved. Because leaving a long relationship isn't just leaving a person. It is leaving a version of your life, a version of yourself, a future that no longer exists in the same form. That loss is real and deserves to be named as such.

The fear of starting over alone can be as powerful as anything else. The attachment system, as Bowlby understood, would often rather maintain a painful bond than face the absence of one entirely. Loneliness is its own threat. And for someone whose confidence has been ground down over time, the prospect of being alone can feel unsurvivable.

What staying costs

Withstanding a relationship that one knows is harmful has a cost that accumulates quietly and is often only visible in retrospect.

The slow erosion of self. The person who has been so long in a dynamic that doesn't meet their needs that they have lost contact with what they actually feel, what they actually want, what they are actually worth. Who has adapted around a partner's behaviour for so long - placating to avoid arguments, working late to avoid going home, monitoring mood before speaking - that their own needs have become an afterthought.

Feelings of shame are common. A sense of having to perform to those around them, to present a version of the relationship that others will accept. A tolerance for behaviour that would, in another context, be immediately recognisable as unacceptable. The gradual lowering of the bar for what feels normal.

None of this happens by choice. It happens incrementally, in a context where each individual adaptation makes sense even as the cumulative effect is significant.

The question worth asking

From the outside, the question can feel obvious - why are you still there? But from the inside, that question misses everything.

The more useful question is not whether to leave, but what is keeping you where you are. What does the attachment to this person - and this relationship - represent? What would leaving actually mean, practically and emotionally? What are you most afraid of? And what would it take to develop the agency to make a choice that is genuinely yours, rather than one made by fear, habit, or the weight of a shared history?

These are not questions with simple answers. They are questions that deserve space, time, and a relational context in which to explore them honestly.

What therapy offers

Therapy cannot and should not make this decision for you. What it can offer is a space in which the complexity of it can be held without judgment - the love and the resentment, the hope and the exhaustion, the reasons to stay and the reasons to go, all of it present simultaneously without any of it needing to be resolved before you are ready.

It can help you reconnect with what you actually feel underneath the adaptation - the needs that have gone unmet, the self that has been slowly eroded, the clarity that becomes possible when someone is finally witnessed honestly.

Some people leave. Some people stay and find a way to change the dynamic. Some find a version of the relationship that is liveable on different terms. Therapy does not prescribe which of these is right for you. But it can help you find out.

Written by Layla Eissa MBACP

Further Reading

• John Gottman & Nan Silver — The Seven Principles for Making Marriage Work (1999)

• John Bowlby — Attachment and Loss, Vol. 1: Attachment (1969)

• Irvin Yalom — Love's Executioner (1989)