Im 18 amd my girlfriend is 19. We've been going out for almost 2 years. We've been sexually active for almost 7 months now. However we have not had sex in almost 2 months. I highly doubt its kus she's sexually active with someone else, because we always spend time together . And on top of that she has always been the extreme lovey dovey type. We do make out and she does perform oral sex on me, but just not sex anymore. Im not being a jerk or anything but as a guy not being able to have sex with your girlfriend is quite frustrating. Its like all of a sudden she doesn't want to have sex anymore when before we would have sex on average twice a week. I understand if you don't want to have sex bcause your tired or not in the mood but can you really not be in the mood after 2 months? It has been getting me really frustrated and I'm stomped and I'm not sure how to approach her and ask her directly.

Please ask her gently, and report back.
Not 'why won't you... ' but more like 'try to tell me what has changed... '
We could guess all day. I can think of a Top Ten but will wait for your reply.