My girlfriend loves me but likes someone else?

Ok so here's the deal, I'm 17 she's 18 , I'm a junior in highschool she's a freshman in college and we've been together for nearly a year now. When she left for college, I was really afraid because I thought that shed leave me for a college guy but she ured me that shed always love me and I've always told her that I'd always love her. Everything was fine until now, she started to like this one kid who she didn't really talk to until now. She's been studying with him for the past week because of midterms and he's really smart and nice according to her but does not compare to me, at leasts that's what she said. She days I'm the perfect guy and doesn't know why she likes him but I think it might be because he's there and I'm not since I can't visit her and I dont drive. Am I doing something wrong for her to have feelings for another guy? I tell her I love her and I always tell her that I'm so happy with her and lucky she's in my life I buy her flowers write on her fb wall telling her I miss her and j love her, and we used to talk every night for a long time but now I'd be lucky to even get more than 10 min. I always say that she's beautiful and I would only love her and be attracted to her( that's what she told me too until now). She and her friends even said he doesn't look as good as me but I know that my gf isn't the type to base relationship off of looks. We just talked about right now and I'm hurt, crushed, and I feel like ****. I don't understand how this could have happened. Lately she's been telling my that she wanted a break because she doesn't know what is out there and how does she know if I'm the one for her, but know she used to tell me that I make her happy and that I was the one and I was amazing but she's doesn't even say anything now and all she does is tell me how she wants to know what it's like being in another relationship. This is the part where I don't understand the most, if she loves me and is happy with me, then why dies she wonder? Help?!