I have a feeling my girlfriend is cheating on me. About 6 or 7 months ago my ex girlfriend started spreading rumors that I slept with her multiple times when I was with my girlfriend which isn't true. She has been trying to break us up ever since we got together and has said a bunch of things bad about me like I slept with my girlfriends friend and I'm gay and just a bunch of stupid stuff. Well my girlfriend cheated on her ex boyfriend when he cheated on her just for retaliation so if she thinks I cheated on her I feel she would do the same thing. I have told her that I didn't but I think she still believes I did in her mind. She has times she is gone that she can't have an explanation for, she doesn't answer my texts or calls sometimes, she has had random texts from guys that I have seen but they didn't say anything but hi or how have you been. I also found out she has been talking to her ex on email and phone but she said it was just to see how he was doing. One time we didn't have sex for like 2 weeks because I was out of town for work and when we finally did she was not very tight like she usually gets after a few days with out sex. am I over thinking or over reacting or do I have something to worry about?