How do you sincerely apologize to an ex without them thinking you're trying to get back with them or fuck them?

Write them a letter.

Apologize for the ugliness. Include a sentence that while your relationship is firmly in the past, you hope that both of you can let go of any pain or resentment from that time, and that you wish him happiness in the future.

Put it all in a letter, and stress that you don't expect a response. You just wanted to let him know you're sorry.

You can't control what other people are thinking or how they perceive a message. Simply tell the person that you regret saying the things you said because you are trying to let go of the past and the pain of the past. If they appear to get the wrong message, set them straight.

Is this an AA project? Because, if so, that's really all about you feeling better about yourself than letting them feel better.

They know what you said was bullshit - and the harsh words helped in letting the partner let go and not look back.

This is all about you - trying to repair your reputation and releasing some of the rightful guilt you have for saying the shit you said.

The right time to apologize is within a short period after it happened - not YEARS. You realized what you said was wrong the next day or a week later - that's when an apology would be heartfelt.

Now? Oh and you and your ego thinking that the ex will want to get back with you after you being such an asshole. Honestly - doesn't sound like you've changed much at all.

If your primary motive in offering an apology is to assuage your own guilt, then don’t bother making one. Such an apology is not a real apology. The relationship is now over and it’s time to move on. What you said and did are now in the past. What matters is that you recognize that you hurt him, are sorry for what you did, and are now resolved not to behave similarly in the future.

R4 here - sorry - you really hit a nerve.

You say you don't want him to think you're trying to get back with them - but you are, in a way. You want to get back in their good graces, just not sexually or in a relationship. So you DO want something from him.

At least acknowledge that. Because you are really not being honest with yourself about any of this.

I've treated my ex badly. I've resolved to treat all my near and dear well going forward. I think it's the best I can do to make amends to him.

lots of good points here. Just contacting him is possibly hurtful, possible not though. Write a letter and keep it BRIEF and mostly about him. You should make a point to remember specifically a way he might have felt or been hurt, and then apologize. That's it. I had an ex do this 10 years after the break up. It was nice for both of us and we exchange social greetings a few times a year now and it adds some peace to a life trajectory.

What R8 said. Make it a real apology and about them, not you

R6 ...what about my post hit a nerve?

OP if what you did is really fucked up, write a killer song about your feelings of regret and shame and willingness to make amends, then release it and let it get play. If/once it’s somewhat successful or it’s been out for a good few years, find a way to let your ex know it’s about them and encourage them to listen, giving no further comment. Shit worked for me.

Then again, my dude was literally in jail for 24 months while all this went down, so🤷‍♀️