levite

It sounds to me like she's conflicted. If I had to guess, she wants to move on, but being in a relationship with you is safe. It's unfortunate for you that she doesn't seem to be able to put these feelings into words.

In either case, I'm afraid I would have to advise you not to prolong the agony. Make it a point to begin a conversation with her with an object of resolving everything not being talked about. If she will talk, great. If not, do your best to be kind. Although she might always say something completely unexpected that will explain everything in such a way as to let your relationship proceed, I wouldn't hold my breath. I think both of you will ultimately be best served by breaking it off. The upside appears to be that you seem like a solid young man, and it should be reasonably possible for you to break this off in a mature and respectful way, so that you can remain friends. I know, that's an awfully thin silver lining to a fairly largish cloud.

But I think in time, you'll both appreciate a clean and mature ending to the relationship, at this point in your lives when so much is changing already.

__________________
Dull sublunary lovers love,
Whose soul is sense, cannot admit
Absence, because it doth remove
That thing which elemented it.

(From "A Valediction: Forbidding Mourning" by John Donne)