RE: the cellphone fight. Here's a line I like to use often, that's very good at diffusing things (my wife and I are BOTH terrible fighters):
"Oh, I'm sorry. I thought we were allowed to disagree with each other."
So many times when we fight, we start yelling past each other, and dismissing each other's feelings on the subject at hand. Just a simple line drawn that establishes our position seems to help -- "Yes, I hear you that you want _________. What I'm saying is, I happen to DISAGREE with that, which I thought was OK. Now, do you want to talk about that, or keep screaming at each other?"
