Why Can’t I Stop Thinking About My Ex?

Thinking about an ex on repeat is usually rumination, not simple missing, and trying to force the thoughts away tends to backfire and make them louder. It’s more common with an anxious attachment style, and it isn’t the same as calmly making sense of what happened. A few minutes of bilateral stimulation can loosen an intrusive replay in the moment.

It’s the middle of a meeting, or you’re waiting for the kettle to boil, and there they are again, not even a big memory, just some ordinary moment from months or years ago. You didn’t call it up on purpose. Weeks can pass without a single thought, then one random Tuesday brings four of them back to back. If you’ve started wondering what’s wrong with you, the honest answer is probably nothing; your mind is running a specific, well-studied loop.

Why does my mind keep circling back to them specifically?

Missing someone and ruminating on them aren’t the same thing, and the difference matters. A 2007 study in Personal Relationships followed 231 young adults whose relationships had ended in the past year and found that reflecting on a breakup, calmly making sense of it, was linked to better adjustment over time. Two other patterns, “relationship preoccupation” and “romantic regret,” circling the same scenes and what-ifs without landing anywhere new, were linked to worse adjustment instead. The study found rumination largely explained the link between a more anxious attachment style and worse adjustment.

Feelings about an ex don’t fade in one smooth line, either. A 2005 daily-diary study beeped 58 young adults at random for 28 days after a breakup and found that loving feelings for an ex eased at a fairly steady rate, while sadness, anger, and relief each traced more of an up-and-down curve, with emotions generally most changeable in the weeks right after the breakup. That unevenness is likely part of why a wave of missing someone can still catch you on an ordinary Tuesday, weeks after you thought you were past it.

If this pattern keeps showing up, not just with this one person but across relationships, it’s worth asking whether it traces back further than this breakup. EMDR’s own theory, the Adaptive Information Processing model, holds that patterns like this usually trace back to earlier experiences that never fully settled, according to EMDRIA, EMDR’s professional association. Our attachment wounds page goes deeper into that connection.

Why does trying to stop make it worse?

Because thought suppression tends to backfire. A well-known 1987 study in the Journal of Personality and Social Psychology had people talk out loud for five minutes while trying not to think of a white bear, ringing a bell every time the thought slipped through anyway. It kept slipping through. Afterward, when the same people were told they could think about the white bear freely, they thought about it even more than people who’d been allowed to think about it from the start.

Trying not to think about your ex works the same way. The part of your mind checking whether you’re thinking about them has to hold the thought in place to check, which is part of why willpower alone tends to fall short here.

Why do the good memories hit hardest?

Sometimes it isn’t pain pulling you back, it’s warmth, which is its own confusing trap. Research on everyday experiences, like vacations, has found something psychologists call the rosy view: people’s memories of an experience turn out more positive than how they rated it in real time, and that shift shows up within days. Relationships likely work the same way. An ex who wasn’t right for you can still feel more appealing in memory than they were in the moment, which is one more reason “just stop thinking about them” undersells what’s actually happening.

What can you do about it right now?

For one specific memory or wave of longing, not the whole relationship at once, a short round of bilateral stimulation (BLS), the rhythmic left-right technique behind EMDR, is worth trying:

• Rate it. On a 0–10 scale, how loud is the thought or ache right now?
• Bring one moment to mind, not the whole relationship, just this feeling.
• Add bilateral stimulation. Move your eyes slowly left and right for 20 to 30 seconds, or try the butterfly hug: cross your arms and tap alternating shoulders.
• Pause and notice what shifted, without forcing it.
• Repeat 3 to 5 short rounds, checking the number again each time.

A 2020 meta-analysis pooling 942 participants found that eye movements like these measurably reduced how vivid and emotionally charged a held-in-mind memory felt. EmEase, a self-guided EMDR app, offers this same technique as a guided practice you can run anytime in the web app.

When is this more than everyday overthinking?

An occasional replay or a wave of nostalgia is ordinary. It’s probably more than a quick technique can handle if it happens most days, if it’s pulling you toward contacting or monitoring them in ways you can’t resist, or if the relationship involved abuse or coercive control. It’s also worth more support if the thoughts are tangled up with the whole process of getting over the breakup, not just the replay itself; the fuller getting over a breakup guide goes further into that wider picture. Is self-guided EMDR safe? covers that line in more detail, and a licensed therapist trained in EMDR is the safer path for any of the above.

Your mind isn’t malfunctioning. It’s running a loop that pushes back when you try to suppress it and softens memories the longer they sit, and both of those are well documented in research. A few minutes of practice can turn the volume down, without you needing to win an argument with it first.