So you're in a pretty sucky situation. You don't want to hear her ramble on about her ex, (girls HATE when guys talk about other girls, so why should it be different?) You might want to mention that to her.

Telling a girl who isn't ready for a relationship, who values your friendship a lot, and has sexual insecurities, that you want to be "friends with benefits," is a BAD IDEA. So don't say it. She is obvisously attracted to you, so if she wants to hook up still, then you are lucky, and she will make it happen.

Most girls feel like if they don't date or have sex with a guy, then they don't want anything to do with them, so be careful to not protray that idea. It seems like she may have a lot of issues, so beware. You seem like a very nice guy, in time she will probably realize what a treasure you are and fall in love with you. ;-) Good Luck!