Whats His Deal?

I have a guy friend, which I have history with. We had a fall out in our freshman year, but we fixed it this year as juniors. I felt my age old crush begin to return, though we can't seem to talk to each other in person. I think we're too scared to face each other, so we chat online. But I visited him at his work over the summer, and helped him when he needed advice. But he got a girlfriend, and things changed. He didn't talk as much, and when he did it was about her. When I'd p by them, he'd kiss her with more enthusiasm. Whenever they'd have a fight, he'd come to me and ask what to do, and I'd help him with a heavy heart. Hurt, I tried to stop talking to him to get over it, but it seems like he won't leave me be. He keeps talking, looking at me from afar. I don't understand if he's trying to keep me as his 'rebound' girl for when his girlfriend screws him over, or if he's trying to make me jealous...? What do you think?