I thought it all a bit vague too. Thanks for asking what I was wondering too NYCinidie.
I agree that this has to stop right now. Even if you haven't had sex, or touched each other in a way that is sexual.... stop, right now. You say you know this stuff, so listen to your self. It sounds like you will end up with nothing if this goes any further.
I am hoping you haven't done anything stupid yet, but one thing seems for sure; you haven't got to the stage where that pain you feel and guilt has solidified and become normal to the point of ignoring it, rationalizing it and turning it into something that rots the very core of your being until you are no longer the person you know and love. You seem to be grasping at trusting yourself!
Now is the time to act. In the company of your therapist, tell her what is going on. I have a mono partner, its possible to get through this with some compromise, some slow movement and trying to understand that the two of you speak two different languages. This other woman will wait if she is meant to be. There is no rushing into this stuff anyway. Especially if you are looking for a long term thing. So take your time... slow down and let your wife catch up for a bit.
Try looking at some "cheating" threads by doing a tag search for "cheating" in the search engine. I suggest it as there are a lot of stories here of what happens when you cheat, what can be done and what kind of process can be gone through.
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