I replied yesterday to this but deleted it because I had to give it some more thought. I wasn't trying to bash you or accuse you of anything. I asked those questions NOT so you could defend yourself to me, but to point you in the direction of thinking about those answers for yourself. I still think it is a bad idea to send the letter. The reason is that if this person did these things to you, and cared about the relationship, you wouldn't have to ask for the apology. That's the reality and it's not a nice one.

The other thing that has to be true is that if he did these things, never apologized, and now is gone off to other things with no remorse (I can only go by what you say in your post), then the other conclusion I come to is that you accepted this behavior on some level. Maybe you weren't happy about the behavior, maybe you did everything you could to have this guy change his behavior, but you stuck around (until now). This tells me that on some level you put your own needs aside while dealing with this person. If the person is now gone, because they left, then the person is either not getting that they hurt you (I believe they DO know, but I could be wrong), or just not caring; or, they just don't know how to maintain their own ego AND fix the situation. I don't know because I'm a stranger; YOU know better than me what those circumstances are. The point is the same: asking for an apology is not going to re-establish the equality in the relationship, because that person is not IN the relationship anymore. Asking for an apology is like saying "you hurt me but if you apologize, we can be OK again, because I'm here for you, always, and if you do it again, I'll still be here, but please apologize".

This is still one person ASKING the other for consideration that is beyond the capacity of that person. This means that you're not seeing that this person is checked out. As long as you continue to not see that, then you are still in this denial which puts you in the position of disrespecting yourself.

And to be clear, you don't come across as a psycho (your words). You come across as a bit self-abasing. This is normal and natural since you're in pain. But you don't want to put that out to someone who clearly doesn't treat you well, and isn't there for you in any way. Doing so is an example of not taking care of your emotional self.

I know nothing of your other relationships. I can't comment on those. I only asked questions for you to consider.