Did she tell you that she would leave if she thought she could? In other words, she is ONLY staying for the kids?
If she stays for the kids but doesn't work on the marriage with you, is that what you really want? If this is what you are perceiving, no wonder you are feeling "used."
Where is the joy and love? The things that brought you together and inspired the creation of children? Is there any right now?
Even though she has hurt you deeply, she put her life on hold for a long time to be a dedicated mom to your kids. Since she supported you and helped you get where you are, it is fair, in my opinion, that you give her this time to create something of her own identity. If she becomes successful, it only benefits you and the kids even if you end up divorced.
I saw on another thread that you mentioned that a "friend" asked you to dinner. What is this about? Just in case one of my possible interpretations is accurate: In your particular sitch, you are still married and cohabitating, presumably sharing a bed. IMHO, flirtations don't seem quite right to me. Perhaps I am working with limited information on this point.
