Brett and I do this a lot. Things will start to get heated and then we'll call ourselves on it. "I'm mad a me, you're mad at you,but we wont back down b/c we feel stupid." Just laugh at yourself and move on.
Our words have such an effect on each other. Just saying one nice thing to someone can completely alter their views on the day and world, and could even save a life. Try saying something nice anytime it comes into your mind. Make kindness a habitual lifestyle, not a chore!