You stop obsessing over someone by making the thought harder to reach and less rewarding once you reach it, not by trying to want them less. Wanting is not under direct control. Access, habit and attention are, and those three are what the loop is actually built from.
How to stop obsessing over someone is therefore less a question about feelings than a question about what you do in the ninety seconds after their name enters your head.
This applies whether it is an ex, someone who never noticed you, a person you had four dates with, or a colleague you have never mentioned to anybody. The mechanism is the same.

Why willpower is the wrong tool
Deciding not to think about a person does not work, and there is a reason it fails so reliably. To check whether you are thinking about them, you have to think about them. The instruction contains the thing it forbids.
What does work is competition and cost. Something else has to occupy the slot, and the old behavior has to get slightly more annoying to perform. Not impossible, just annoying. A phone that requires you to log in again is enough friction to break a lot of automatic checking, because most of it is automatic rather than decided.
The second reason willpower fails is that obsessing is doing a job. It usually feels like problem solving. If I go over this enough times I will find the sentence that explains it, and once I have that I will be able to stop. There is no such sentence. The search feels productive right up to the moment you notice you have been running it for five months.
Nine things that reduce the loop
- Change the room. Most people spiral in one specific place, usually a bed or a particular chair, at a particular time. Move. The physical setting is doing more than it seems to be.
- Put friction between you and the information. Log out. Remove the app from the home screen. Take the shortcut off your bookmarks bar. You are not trying to make it impossible, only to insert two seconds in which you can decide.
- Stop narrating them to friends. Every retelling rehearses the story and keeps it warm. If you need to talk, talk to one person, and give it a stated end point rather than letting it become the theme of the friendship.
- Move until your breathing changes. Not a wellness suggestion. A walk that leaves you slightly out of breath interrupts rumination more effectively than an hour of trying to reason with yourself.
- Answer the question you are actually asking, in one written sentence. Usually it is what am I hoping happens. Write the honest version, including the fantasy where they turn up in the rain. Seeing it in your own handwriting takes a surprising amount of the charge out.
- Book one human per day. Not a big social life, one contact. Coffee, a phone call, a walk with a neighbor. Obsession thrives on unstructured solitude.
- Take back one thing that was yours before them. A place they never went, music you stopped playing, a hobby that lapsed. Reclaiming territory does more than avoiding reminders.
- Write the flat log instead of the meaningful one. Facts only. What happened, what was said, what you did. No interpretation and no reading between lines. Reread it two weeks later and it will read like a different story than the one in your head.
- Handle the two in the morning version differently from the two in the afternoon version. At night, do not make decisions, do not draft messages, do not reach conclusions. Nothing you conclude at that hour survives daylight, and the messages sent then are the ones people most regret.
You do not need all nine. Three, done for three weeks, will noticeably change the frequency.
How long does it take to stop thinking about someone?
Nobody can give you a real number, and the confident ones on the internet are inventing it. What varies is contact, how the thing ended, how much of your daily routine involved them, and what else is going on in your life.
What helps more than a timeline is a better measure. Do not track intensity, track frequency. Intensity is misleading, because late in the process you can have one enormous day that convinces you nothing has changed. Frequency tells the truth. If you were thinking about them forty times a day in March and it is nine times a day in May, that is progress, even if those nine are still sharp.
The other honest note: the last stage is not sadness, it is indifference, and indifference tends to arrive quietly. Most people cannot say when it happened. They notice a week later that a song played and nothing much occurred.

When the obsession is not really about them
Worth checking, because a fair amount of obsessing is not about the person at all.
Sometimes it is about the ending. An unexplained exit leaves the mind with an open file, and open files get reopened. Sometimes it is about the version of yourself you were around them: more hopeful, more interesting, at the start of something. That is a real loss and it is not the same as losing them. Sometimes it is timing. People fixate hardest in the periods when the rest of life is thin, and the fixation is the most vivid thing available.
And sometimes it is injury rather than love. Being passed over stings, and the mind treats stings as problems to solve. If the fantasy is mostly about them realizing what they lost, rather than about ordinary Tuesdays with them, that is a clue about what is actually driving it.
If the thoughts are relentless for months, if they push out work and sleep, if they lead to contact you would not want described out loud, or if they come with thoughts of harming yourself, talk to a doctor or a therapist. That is the right tool for that job.
The trap of making them a project
The most convincing form of relapse looks like self improvement. Getting fit, sorting out your job, becoming interesting, all quietly aimed at a moment when they see the finished version.
The work is usually fine. The addressee is the problem. Anything built for an audience of one stalls the moment that audience does not show up. When you notice it, keep the plan and change who it is for. Practically, that means asking whether you would still do this if you knew for certain they would never hear about it. If the answer is no, it is still part of the loop wearing better clothes.
Is this the same for everyone?
No. The patterns here are the common ones, and yours may sit somewhere else entirely. Treat any general answer as a starting point to react against rather than a verdict, and pay more attention to where it does not fit you than where it does.
Where should I take this next?
If it keeps coming back, or you would like a second read on your particular version of it, that is worth a conversation with somebody rather than another search. Anything that is genuinely distressing belongs with a professional.

One clean way to close the file
Some questions keep coming back because they were never answered anywhere outside your own head, and internal answers do not stay put.
If yours is whether the two of you were ever going to work, the Two-Sign Compatibility Report sets out your sign and theirs in writing, including where the strain would have shown up and what the good version would have needed. It is something you can read once and shelve. The 144-page compatibility matrix is there if you would rather look up the pairings yourself, this one and the ones before it, which is often when the pattern stops being about one person.
Where to take this next
If you would rather talk it through than read about it, Seraphine Vale and the rest of the roster read by live chat, and how a live reading actually works explains what to expect before you start one. There is more in the love relationships library, and if you are not sure what you are looking for yet, the quiz is a two minute way in.
