Friend's wife cheated at poker...?

Anybody with poker knowledge, please help. The other night, some friends and I were having a small poker game. We all bought in for $20 each with $100 going to 1st place. My friend and his wife are among the players.

After a while, it comes down to my friend's wife and me. We're headed up and I have a weak hand (5,9 off suit). She's dealing as well. Flop comes out 2,10, and J. She clearly checks first and I check after her. She then bets a stack of chips BEFORE laying down the turn card. I argue that she can't do that. She says why not? I argue that you can't check and then change your action once I've acted. She had to deal the turn before she could bet. She keeps saying that she never checked first which was obviously a lie. This starts turning into a legit argument.

Finally my friend pulls me aside and says "let it go man, she's drunk." I give it and let her play the way she wants. I end up folding and losing a few turns later after going all in and getting beaten. (I had ace, 10 suited and she had a 2,7 and got 2,2,K,9, J on the board)

It killed the whole mood that evening and I'm sorta heated over it. Not so much about the $100 but how my friends wife thinks she can behave like that and think being drunk is an excuse to cheat. Poker players, did anything I do was wrong? How should I tell them that what happened wasn't cool?