[Harmony♥]

Firstly, just because they aren't alike doesn't mean they can't be together. My boyfriend and I are utter opposites, and we're going on 3 years together next month. Opposites really do attract, sometimes.

Now, my advice to you would be to wait. Obviously, he sees something in this girl and it wouldn't be fair to try to be with him right now while he's in a relationship. Not fair for you because then that would make him a cheater, and nobody wants a cheater. Not fair for her because she'd be the one getting cheated on. Let's face it: you wouldn't like it very much if another girl was trying to get with your guy, would you? Probably not.

Just wait until he ends his relationship with this girl. From the sounds of it, it won't last very long. Have patience, my dear. Your time will come.