UGH! Guys can be such a**holes!
I know exactly what you are going through, because I spent most of my 20s with someone just like him. I did love him SO much, and I think part of that was because I could never quite make him what I needed. There's something to that whole idea of "hard to get". When it's just out of reach, it makes you insane trying to grasp it and keep it. And of course they always come back begging whenever you finally start to move on and are able to finally sleep in your own bed!!
Trust me when I tell you, you should do your best to make a clean break now, because this could literally go on for years and years (him coming and going and severely breaking your heart every time), and the next thing you know you'll feel like you wasted your whole youth on something that really wasn't worth it.
I agree with the other ladies that it's best to focus on YOURSELF right now, really take care of yourself!!! But if I were you, I wouldn't turn down any dates from nice guys who ask!! There's no cure for an old love like a new love!
If nothing else, it'll be good for your self-esteem if you get some interest from others!!!
There's always someone else out there for you, girlfriend! If he was your one true love, it wouldn't be so friggin' hard to be with him!! Please trust me!