Welcome to PC. You have definitely found the right place.
I was in the same place you are a couple months ago. I lost my partner, and a couple friends because of the break up. She is now not talking to me at all, and like you, I just don't get it.
All I can tell you is that you need to concentrate on yourself. You need to heal yourself, and let her go.
One thing that I have found helpful is to blog. I write everything out, and get it out of my system. There are blogs you can create here on PC. That's where mine is. If you want to read it, it's under justjoanie and the name is: Learning to dance in the rain.
Something else to consider.... Go talk to someone about it. Do you have a therapist that you see? If not, it may be a good idea to find one that you can talk to. He/she will give you good advise on how to heal yourself, as well as give you an outlet to vent.
You can come here and vent anytime you want. We are here to listen.
I hope you stay on here at PC and find it as helpful as I do.
((((((((((octavarium))))))))))))
Joanie