It kinda just happened to me. While she doesn't seem entirely certain, she did tell me that she 'wasn't sure if she loved me as anything more than a friend'. Not a good feeling, but I'm giving her space to think about it - since like I said, she didn't seem 100% sure. She's also against committing to an LDR, which is fair enough. We may end up in the same city next year, though, so if we do . . . who knows, it still may happen.
I think the most important thing in these situations is to strike a balance. Backing off completely basically ensures you'll never have a chance, but continuing to push and niggle at her is also a dumb idea, because that's just going to annoy her and show her you don't respect what she's said to you.