What would you do?? (Girlfriend stuff)

[J-Man]

Ok, I've been with my girlfriend for 2 years. For these 2 years my biggest fear has always been for her to fall in love with somebody else. I recently found out that she's starting to fall for this guy. One of the biggest problem is it seems so much like she was just using me... because she used to be sort of controlling.... like didn't like me on the computer and stuff like that, she wanted me to "be with her." But now that she's found this guy, she talks to him all day... be it on the phone, on the internet whatever. And never cares that I WANT TO BE WITH HER(I mean be with her physically, not be with her as in date her... even though I do). It's like anytime we get into an argument she doesn't care, she can just go talk to him. In addition, there have been a series of lies about her feelings towards him and stuff like that. I know it's arguable that she's not doing anything wrong when she starts to like this guy... it's her feelings, ya know? But, she doesn't take care of me about it or hold me or anything... that is her fault. Especially since she's always assured me that this would never happen. I think the worst part of this whole thing are times like these.... right now, almost everybody I know (even people in my family) have their loved ones... my dad, mom, stepmom, stepdad, brothers, friends, her.... just not me. And I just feel so trapped because I have no idea what to do. I don't feel like I can be with her (even if she does pick me over him) because of what she's already done to me. But also I'm not sure if I can live without her. So that's my rant... but I wanted to know what you all would do if you were in my situation. Sorry for the long, incoherent babble.... it's just sort of hard for me to type because I also broke my wrist yesterday(I'm going through such a GREAT time in my life). Anyway, any feedback is appreciated.

Jeremy