"She volunteered reassurance that she didn't cheat on me this weekend, that OM wasn't at her presentation. Hopefully some new intel from the next few days will reveal the truth of this claim."
Did it ever resonate that cancelling the CC had nothing to do with OM/cheating, but that she did not honor the agreemsnt she had just made regarding usage of the card?
It is not about what you feel should work in your M. It is about doing the work that gets the right results. Do what works!