One thing that helped me was realizing I don't know what's going on in other people's heads (and often don't want to know :-) so deciding they are being deliberately rude or are playing some game at my expense doesn't serve me.

I try to remember the idea of "kick the dog" which happens when the husband gets yelled at by his boss and can't respond without threat of getting fired, comes home and yells at his wife because it's "safe" and she yells at the kid and the kid kicks the dog. It all goes downhill and that can happen in any situation. The person that doesn't like you at work can feel unliked by someone else and is taking it out on you.

Projections happen all the time; I still remember when I called and yelled at a grocery store manager because my fifty cent cat food was packaged separately and overlooked when I picked up my bags and left without it, realized that was a pretty extreme thing for me to do (I was afraid of the phone and of anger) so I thought long and hard and, sure enough, something had happened earlier at work that set off a chain of such responses by me.

The adage to smile at your enemies, it will drive them crazy comes to mind. I like to thank people for sharing with me when they say something (true or not) I don't like, it confuses them and shuts them up? Come up with a funny response in your head, substitute "blah, blah blah, blah, blah" for what they have said or some other private joke ("Easy for your to say!" or "And your mother wears combat boots!", some non sequitur to remind you that what they have said/done is about them and their issues, not you and yours).