About my relationship...?

I'm a rising sopre at a boarding school in PA and a couple of days ago my girlfriend who lives in NC told me that she doesn't know what she wants right now and she needs a break and she said she's not sure if she can be fully committed to me for her life and etc. I really love her but there's about 60days left till school starts when we can actually see each other...it's like i don't get it just a week ago she wasn't like this and now she just wants to talk after the summer and it's really heartbreaking I can't even do anything like we've been going out since april 15th and since the break started we were in sort of a long distance relationship and in the beginning she said that we'd make this through and everything was positive...I just don't know what happened to her...any advice..?