I think that @blueiiznh is right when he says your lover was probably in a depressed state. He may have many issues to resolve with his ex. He may even have used you to help him get away from his ex. Maybe it gave him something to go towards in order to get away from the ex. More motivation.
If he is depressed, he will feel like he doesn’t deserve a relationship. He may be trying to punish himself for how he treated his ex. He may be remorseful about what he did to his ex and doesn’t want to do it to someone else. I hate to say it, but he sounds a bit weak using other women to help him get from here to there.
If he believes this about himself, then he will be hating himself. That’s where the YDB comes from. It’s as if he’s giving you a gift when he breaks up with you. Of course, he is not taking the time to find out what you really want. That’s typical of the depressed. You’ve already taken the time to reassure him about what you feel.
In my experience, when you’re depressed, you don’t believe what people say about you. You’re really down on yourself. At the same time, sex is very important. It’s the only thing that makes you feel at all connected to anyone. If he is doing that, I would expect him to be showing up at your door from time to time to get a sex fix.
But depression is difficult to deal with, especially if you don’t agree that you are depressed. I would urge him to see a mental health professional. Maybe he needs meds. Maybe he just needs therapy. In any case, whether he’s depressed or not, therapy should help him move through the stuff he’s dealing with. Is there any chance he would go?
I think it’s almost impossible to know, at this point, how much he is into you. I bet he has no clue. If he’s keeping a lot of contact with you, I think that means he’s definitely interested, but if that contact is very surfacy, it can’t be very satisfying for you. You want a real person, and he’s a caricature of that right now.
Will he be able to come back and be present with you again? Should you wait for him? Well, if he’s really sick, then I would lean towards waiting. If he shows a real interest in healing by going to therapy, then I would risk waiting. But if he does not seem to be taking any conscious steps towards getting clear with his shit, I think I would seriously think about cutting all ties with him.
Of course, if you can’t cut all ties, and you must run into him often, that makes it really all that much worse. In a way, you’re screwed. Damned if you do, damned if you don’t. It’ll be very painful for you. You might try to do things that would hurt him, like dating, but I have no idea how that would work.
It may be that, for the time being, you don’t have any choice but to continue to work with him. Urge him to get therapy. Support him through his situation. Assume that when he gets straight, he will love you again, and not be so “confused.” Assume it, but don’t expect it. Just recognize that you are making the best of a complicated situation.
Meanwhile, take care of yourself. In all meaning of that sentence. Yoga. Therapy. Meditation. Exercise. Hang out with friends. Pursue some interest—educate yourself, or throw yourself into work. Spend more time with your kid.
It’s a very tough time. Lot’s of pain and anxiety. Deep breathing. I’m sure you know how to do this. Make sure you practice. Often.
I wish you the best of luck.