It just kills the watching experience. Just say, "look, I'm going to act like an idiot during the game-- so if you don't like it, either fake that you didn't hear or go do something else." It won't go over well with her, but it will set the ground work for those moments when she calls you out during the game. You can tell her you warned her and she will realize you were right and either keep quiet thereafter, or she will find something else to do.