Take driving for example. I've really tried to drive with a higher level of compassion and understanding for what my fellow drivers might have going on that leads them to make poor driving decisions. This is rather easy to do in where we live as, even at the height of traffic congestion, the traffic here is never all that bad. However, a couple of weeks ago, when dealing with the traffic around Detroit--which could take an already long drive and double the time--I found myself shouting out curses and aggressively (almost punitively) driving almost immediately. I was deeply disturbed to see how quickly those older, harsher driving strategies came out.
Sadly, this can happen with games all too easily as well. An otherwise pleasant game can suddenly turn the moment that I feel directly attacked. Part of my issue is that I don't take a proportional response, but rather go all in on a feral attack to make certain that the person not only regrets their decision, but realizes that they never want to take such an action against me again (although, there are some people who thrive on the conflict that my sort of response generates). Often, I will hold the grudge beyond the end of the game session in question if I feel that the perpetrator does not yet fully understand the wrath that they've unleashed.
Still, I'm trying to be better. That raging monster within me is a bit of an embarrassment, and I can use my own fear of embarrassment against myself to help me to some degree. It also helps for me to put myself into the perspective of my "attacker." Often, working at realizing what's motivating such an "attack" goes a long way at defusing my rage and engaging my compassion.
And yet, don't make me angry; you won't like me when I'm angry.