UNFAITHFUL?!?!

hey everyone,
I am having a generally decent relationship with my girlfriend who I have been dating for three months. She is my first love and she is a great person because she cares so much about other people. Lately, however, I feel like she doesn't love me. There are a few reasons for this...them being that she goes out to the movies, hang out with, etc. some other guys that I am unfamiliar with. But I feel like she doesn't care about me because she doesn't even TELL me half the time that she is doing it! Her friends and family are usually the ones to tell me. I'm losing trust and hope very quickly. what should I do without sounding like a complete jerk? Thanks. Tweet