Could it be a reaction to high levels of agitation? What other meds are you on and have you always been this way?

I get really annoyed with people too - probably a lot of BPD do?, I do not have a real method to change my internal reaction though, just my external. I know when I am experiencing really high levels of agitation it is much worse.

One thing I do pretty much all of the time now, and I think it is more a form of crappy defense mechanism to negativity (rather like splitting) is I immediately rationalize why someone would have done something rude like that. Like with the door thing, I might go to myself: oh they probably thought it was more polite to be less obtrusive and quiet. It doesn't have to make a ton of sense and I don't really seem to be in much control of it, its just sort of developed on its own...

But maybe a positive way to try to do it would be when you look at a person and you have a negative thought, and you realize it, try to give them a positive. Just one. Challenge yourself! Sort of like critiquing someone's art work or writing. Even the really crappy stuff.