:confused: so my girlfriend isent cheating on me really, but my friends keep telling me she is all over guyes and I don't know what to do

Talk to her about it and tell her that it bothers you. Communication is the most important thing in a relationship, if you can't talk to her, who can you talk to?

If she is in another city, how do they know what she is doing?

If you are questioning it for a second, then there are obviously trust issues. Take the time to talk to her.. see what she says. I think it is time you decide who it is you trust... them or her??