I'm so sorry that happened.
Have you and she discussed taking some time apart to facilitate the transition to friendship? Or does she want it to be an immediate change?
It could help in the long run to take a break now, if only to have a more solid handle on your feelings and wants. If you really want to be able to be close friends with her in the future, you might not want to jump into the role she wants from you while you're still dealing with your hurt.
Best of luck.