After a match of serious competition in which there is yelling, animosity, pain, joy, in your face celebrations etc. can you go out and have a beer with your friend (especially if you're the one who lost)? I've found that after a match like this (even against a friend) I don't want to talk to the guy too much. But the next day everything is as before. The same apparently works vice versa with some friends. What about you?