Jeffrey Eugenides said this quote

Find the Bad Guy means how, when you’re arguing with your spouse, both people are trying to win the argument. Who didn’t close the garage door? Who left the Bigfoot hair clump in the shower drain? What you have to realize, as a couple, is that there is no bad guy. You can’t win an argument when you’re married. Because if you win, your spouse loses, and resents losing, and then you lose, too, pretty much.