1. Own your story.
Whatever you're telling yourself about what that person did, or said, or how things went at work or on the road or with your partner --- the story you're choosing to tell yourself about what all of that means is yours and yours alone.
This is both annoying, because it's always much easier to blame other people for the things we choose to think, and fantastic -- when you accept responsbility for your own story, you discover that you can choose to change it into something that makes you feel a hell of a lot better.
2. Don't assume ownership of someone else's.
It's equally as liberating to realize that you have absolutely ZERO control over the tale someone else chooses to weave about his or her life.
Frustrating? Sure. It would be lovely to be able to manhandle someone else's story; how nice if we could make everyone around us feel amazing and fabulous and loved all of the time.
However, we have no more control over that than we do over causing their misery. They just like to tell us how miserable we've made them, which makes it a bit harder to follow this rule.
You own your story. They own theirs.