i think its really wrong.. i even told him that he should just tell his gf how he feels about her trying to get in his pants and stuff, but he just decided to go w/ "you creep me out. its over" -__-Disguise it as much as you want but this guy is completely wrong for you. He's great as a best friend and he seems to have proven that but he is terrible as a boyfriend.
You asked if you should be best friends with him still. I would say that yes, you should, as long as he starts acting like your best friend, because I'm sorry, honey, but telling you he'll break up with his girlfriend to make you happy surpasses being a best friend. He's clearly immature and indecisive like I said if he's so liberal with his own conscience about breaking up and getting back together left, right and centre with girls. He doesn't think about the long-term consequences of his actions. He's a guy who thinks "I react to the situation at hand and not actually try to make it better".
After he talked about what his ex-girlfriend did with you, did you not think it wrong of him? That only three or four days ago or whatever he was all keen to get back with her and as soon as you show the tiniest bit of upset about it, he instantly throws her away like trash and talks badly about her? Don't you think that's wrong? It shouldn't matter between the two of you what went on with her. It's none of your business if she tried to give him a handjob or whatever. The problem at hand is the fact that he's confusing you and not what his girlfriend is like.
He's immature. Really, you're good as best friends but this will never work out for you.
even his girlfriend told him that she would try to fix her problems and then she woulda wanted to get back together, but he just passed it along as if "damn she's so obsessive and weird! she wants to go out still! " doesn't he think that she loves him!? -__- [ok and yeah she wants to get in his pants] at least she was trying to fix things, if only she knew the problem. which he didn't even bother telling her what was wrong, wtf.
yeah i think id waay rather stay best friends w/ him then a girlfriend, if he doesn't even know how to treat em right. or his best friends! iv always been there for him, but once he's fine and dandy, leaves to go out w/ his guy friends and then comes back whinning to me about how "omgod my brother is such a jerk and this girl blah blah" -__-