If you feel that strongly for her, I would take some time to think things over on your own (you sound very emotional), let her do the same and make sure she has your contact info. I wouldn't pressure her or anything. Hopefully you had the chance to at least give her the opportunity to reconnect and left things on a good note when you were exchanging congratulations on school completion. Don't blame yourself. Just leave it in her hands and if nothing comes of it, at least you made yourself available. I don't think you should be upset at what could be something you were just going through due to this anticipation of transition/graduating. Open yourself up as well. She may just be someone you connected with for that time, but there are still people out there for you to meet you haven't met yet. Best to you.