I have been dating a girl for a while now and she is in another state.What do I do if i like a girl with a bf.?

I have been dating a girl in the northern part of the U.S. and I have been having dreams of a pretty,beautiful,amazing girl named Taylor Jennings,but she has a boyfriend.I thank she is awesome,and in my Language Arts,Geography,Math,AVID and science cl I sit next to her,but I'm not sure if she even likes me as a friend.I don't want to break my girlfriend's heart but my heart is just kind of dissolving.So should I stay with my girlfriend or go after this other girl.I'M ONLY 11 SO KEEP IT APPROPRIATE