Steve85 is dead-on, here. So what if you made an "Agreement"? You weren't in your right mind and, Oh by the way, you're a different person, now (I hope... or soon to be one).
If I can backtrack and recover from telling my WW I "freed her from her wedding vows" (ouch, yes... I really did that in the very early post-BD stages), then you can sure as hell backtrack from "agreeing" to move out of the MBR.
She's having an A with another man! How much worse can things get?!?
See my previous reply to Steve. I busted the first affair and she hasn't seen him again. I believe she is seeing someone else but I can't prove it.