The answer is simple. You can not be friends with someone you are still in love with. Her insistence on being friends is mainly to relieve her own guilt. It doesn't benefit you whatsoever, at least right now. It's a win/lose situation.
She wins (no guilt), you lose (pain, no recovery).
If she broke it off with you then she needs to accept the consequences. That means no friendship, no contact, POOF -- you disappear from her life. Cut off all contact. No IM, no text, no calls, no cyber stalking, NOTHING.
While you implement no contact, you need to focus on rebuilding your confidence and self-esteem.
Lastly, I ask you: "What can she offer you as a friend that you can not have with a REAL friend?"
Answer: Nothing.
Cheers.
Jarbarian...as always I bow. Your posts help everyone, thank you. MizBex