You did awesome. Let her allow herself to believe what she wants - she probably really doesn't think you are cheating, she probably just wants to add more drama.
I think you are really on a good track if you can continue to stay calm w/ her and react "as if" you could care less that she's acting like a dumba$$.
Me: 38 H: 35 S4, S5, S10 Bomb 01/07 Wanted D - nothing would change his mind Numerous A's prior to D bomb; EA prior/during D bomb Piecing 04/07 Deployed for a year 05/07 Still Piecing 2010 M 11 yrs 05/10