Ex wants him back after knowing he was with me

[rezna]

Okay, here's some background.

I was just in a 5 and half year long relationship, was engaged to be married (wasn't really, though, this guy was pretty messed up), and just broke up in May. I've been single since May. I had a huge crush on a guy that I've known for years, and basically started to pursue him as a friend to get to know him better and see if maybe there was a connection there. I've liked this guy since I met him, and basically liked him during my long relationship I just got out of.

The guy I like just recently broke up with a girlfriend he had been with for a year. She broke up with him in February, which was really hard for him because he liked her a lot. He has described the relationship as being somewhat good/somewhat bad. He says certain things with them clicked (I'm assuming the sex is what he's talking about), but other things like compromise, communication, pretty important things, were bad. He even went as far to say that when he hangs out with me our communication is light years better than what he ever had with her. The two of them had actually been having sex ever since they broke up, and pretty much went all the way up to this month.

Him and I ended up getting frisky, had sex twice, and it was great. This made him realize that he needed to cut things off with the ex permanently. He had a talk with her about it, let her know that he was interested in me (even named me, described me, etc to her, which is sort of weird). He said she was very sad about it. For the last few months him and I have been hanging out, sort of courting each other, all the while he's still having sex with his ex, has sex with me, then tells me that he has been having sex with her. He said he's not the kind of guy to have sex with more than one person at a time.

Well surprise, surprise, guess who wants to get back together with him? She's now saying she wants to be with him again.

So I'm in a shitty position now. I really like this guy, feels like he could be pretty close to the best thing I've ever found, and his ex has her claws very deep in him. He even says she's got her claws in him, that exact phrase. It really sort of bothers me that he was able to have sex with me, in the midst of this situation, to share such an intimate thing wth someone you really like, yet is so easily able to entertain the idea of getting back together with his ex.

What the crap do I do in this situation?

[vashti]

he's still having sex with his ex, has sex with me, then tells me that he has been having sex with her. He said he's not the kind of guy to have sex with more than one person at a time.

feels like he could be pretty close to the best thing I've ever found,

I think you need to work on finding better than your personal best. It might help improve the quality of you didn't settle for guys who were having sex with someone else.