^^^Not a bad tactic either. :P
Thirded on principle alone. Mutual respect--no special pleading on this very thing. She's gonna call you hypocrite for things, I'm sure of it. Don't let her get away with the same thing. The idea here is to limit how much she thinks she can get away with now, so later on it doesn't get much worse. And yes, her vindictive behavior *will* be worse.
Otherwise she's going to add this into her normal repertoire when she starts acting like your mother (or a bratty daughter depending whose dominant)....on a powertrip...all the time...while invalidating every little thing you say and do. God only knows what she'll resort to next.
When one of my pals tied the knot a couple years ago, he didn't try to reign in her compulsive shopping when it was still "negotiable", and he's paying dearly for it now. I'm not sure how much longer they'll stay together. Maybe a year, tops IMO. Don't even get me started how she won't settle to save money, and acts like she owns everyone and everything.