coffee_, get the DR right away - and read it cover to cover as fast as you can absorb it.
Zues is right - withdraw and go dark, you've really got nothing to discuss at the moment. She's cake eating - and has all the benefits of both sides.
In the meantime, you've got some hard decisions to make. You've got to figure out a course of action based on possible ways she's going to go on this.
My W never admitted to her A (in fact, denying it), while also telling me it was none of my business. I too had all the proof I needed.
IF we ever got to a point of reconciliation, that would become a major hurdle I don't know if we could ever move past. Because, she's not going to give it up. She's put herself in such a position that it would be very hard to do that.
I've got to come to grips with moving on - and keep her damage to a minimum. She's trying to inflict as much pain as possible. Expect the same could happen.
You're in a good spot for the moment because she's at least discussing MC, and making things work. That's huge. You haven't been fired - and it's possible that her A is so shallow that it can be dropped and was momentary insanity.
Also consider a DB coach - this is exactly what they're perfect for and can help you make the right decisions moving forward. This is a critical time, and you seem to have the gift of time so use it wisely.
Me: 58 Her: 59 Kids: 0 Dog: 1 ILYBINILWY: 9/15 D Bomb: 1/11/16 (found out filed) Verified OM: 1/11/16 Moved out: 1/11/16 (thought it was temporary)