I honestly don't think she wants a divorce, nor do I think she really wants you to give up on her. She doesn't want to face it that living like boother/sister really is not right. But I don't think she really knows herself why she has become the way she is, but at the same time she is really really scared to face that. Lets face it, its really hard to change. change is not easy. Nor will it be easy on your part either.
Annette who just has a feeling that your W really does want to save the marriage, but is scared.