[Atokad]

I agree with Nicole, first and foremost you must talk to him and see what his deal is. If he doesn't commit to you, then yes, I've had a friend like this before. He treated some girls terribly and kept some of them on "the hook" as it was referred to by How I met your Mother. This is where they want to keep you around in the case that he tries for a relationship with another girl and she doesn't want one, but he doesn't have to be alone as long as there is another girl waiting for him.

But that was just a guy I knew, and it could be a different case with what you are in, as you really do need to talk to him one on one and figure out what he's thinking. Don't leave until you have a real answer!