Is it wrong for my girlfriend to dance with her guy friends or am I just over reacting?

I love dancing and my girlfriend loves it even more. We fell in love on the dance floor and have been dating seriously for 6 months and want to get married when we get out of college. I trust her with my heart and being and know how strong our relationship is and is not in question (event I wish not to describe). Now she is going to college and will be away from me for a year. When she is at parties she likes to dirty dance with her guy friends and this really hurts me, I find myself wishing to never dance with her again. We have talked about it and because she is an overachiever and puts too much work on her plate she uses the parties on the weekends to relax and enjoy herself while I'm not there. But she does this by grinding with other guys. When I asked if there was anything she could change so I didn't hurt so much she says it is just dancing and she makes the guys understand she want to marry me and it is the way she has fun at parties. But it hurts and I can't get over it.Is it wrong for my girlfriend to dance with her guy friends or am I just over reacting?
high school is where you grind everyone who comes by....in college and seriously dating someone is not the time for grinding with other guys. you need to talk to her again and make your point clear, then try talking to her ';guy friends.'; if you all can't come to an agreement then try and figure out something else you can do with her that is equally fun, and less hurting to you. if not....Is it wrong for my girlfriend to dance with her guy friends or am I just over reacting?
maybe is wrong to react on that problem you must trust your girl friend on what the things that she do
Just dancing, what so big deal?

If sleep with guy then u just worry lah...

Just dance only, u still want to angry with her?

Please...

If she love u then she will respect u and never did somethings to hurt u...