GF intimacy issue

Hi,
My gf and I will be celebrating our six month anniversary this Friday.
A little background ... we are in our late 30s, both professional, both athletic, and it seems we were made for each other.
We joke and say that we "share the same brain", because we tend to say the same things, at the same time, we know exactly what each other is thinking, etc.
It is great!
Except for one thing ... she has no interest in being intimate. For a while, this was not a problem, as there were some complications, which did not allow us to be intimate (medical reasons). Now that things have gotten better, still nothing.
A little about our seperate pasts. I have a limited history, where she has, what she says, is a quite experienced history, that included several one night stands, short term relationships, etc. She was very sexually active and even when we were first talking and dating, she would talk about how much she needed intimacy, how often she used her "purple friend" to relax, etc.
But, for the length of our relationship, except for the two months, due to medical reasons, the intimacy has been few and far between. My question is, if she was so sexually active and needed sex quite a bit, even with strangers, and with her "purple friend", why doesn't she want it now, when it is so readily accessible?
I know what you all are thinking ... "you need to talk with her about it". We have talked about it, a few times. But, for some reason, when we do, she gets upset (mad and standoff-ish), and nothing ever changes. This morning, as we were getting ready for work, she asked how I slept last night. I was not tired, so I stayed up for a while watching tv, as she laid on my chest and fell asleep quickly. She then responded with, "you must not have been able to sleep because you were probably wanting to be intimate and being a bad girlfriend, I just fell asleep, as always." So, that tells me that she recognizes the fact that there is an issue. But, what gets me is, she is not doing anything to help resolve the issue. I have tried several things, to no avail. And, honestly, I am starting to get pretty upset. I find that I am in a bad mood more often and starting to become standoff-ish.
We are still very good together and I think the world of her. It is just this one thing, and it seems this one thing is turning into something HUGE.

We were at the mall this past weekend and decided to stop into the Jared store to look around. Since then, we have been talking more about getting engaged, marriage, kids, etc. This is not the first time we have talked about these topics, but these topics have been discussed more often, since going to the store and looking. I am asking myself, how can I commit to this person, with this issue that we have now? Would I be willing to live with this for the rest of my life?

Does anyone have any suggestions for this issue?

Thank you!

hmmmm, what was the medical issue?

You mean she's frigid? No matter what it is, definitely needs to be resolved b4 any further progress.

if previous reasons were medical, do you think she is scared to have sex? scared it will hurt/affect the medical reason? also, do you kiss a lot? if you do stuff but don't go all the way, maybe you just need to give her more time. if you are not even intimate in kissing, etc, maybe what she really wants at this point in her life is just companionship. there's this book about different kinds of love, i dont know what it's called, but it talks about different kinds of relationships based ratio of passion, intimacy (like, closeness not in the phyiscal sense) and commitment. the ideal one is obviously a balance of all three, but there is one kind the author talks about that is just intimacy and commitment. i dont know maybe you are on different pages about what you want out of this relationship? whatever you do, i wouldn't put pressure on her about it. try to take small sexual steps if you can. and talk about what you want out of the relationship.

And why are you together again? What kind of girl doesn't want to be intimate? I don't understand lol! She sounds a lot like my ex. Been there, done that. I think you need to ask yourself why your in a relationship with a girl that doesn't want to be intimate.