The principle for Day #42 on the 101-day book report says: "When you get into a conflict, remove yourself from turmoil for just a moment and think about your higher purpose."
I remember a great revelation I had some years back while I was going through my divorce: I am going to lose every argument I get into from here on out. It didn't matter how valid my case might have been at the time, I was just screwed. And like a lawyer in some kangaroo court, I wised up and stopped objecting.
If you get into it with somebody, be it your boss, your spouse, or your teenager maybe, just excuse yourself for a moment. Go outside and think about how little spilled milk is going to mean when you retire on the golf course some day.
It's ok. Let them land on the deck and declare their empty victory.