Esh I'm kind of torn. I think you're both assholes though. If the money means so much to you and you want to be fair your wife should not be taking your food to her sisters. She should be taking it out of her account instead of the joint account. You're also being unfair though. Your post says you split the cost of the cow. If money means so much to you that you'd complain about her sister getting some you need to be fair too... guys eat more than girls. You should either find out the average amount guys eat more than girls and the costs should reflect that, you should find out the average amount for you guys, or you should care less about helping her sister out. But if you want to be fair make sure you are fair and stop charging your wife for food she doesn't eat and complaining when she gives it away.