I'm exactly the same way. I think many of my (apparently high) standards are common sense and I get pissed off easily when people don't live up to these standards. (I'm sorry but didn't we learn when we were kids that lying is bad and we need to be respectful toward others?) I didn't even accept that my standards were high by most people's standards until I became a teacher and saw how high schoolers behaved.

I've yet to find a successful way to deal with this train of thought but I am working on some tricks that are helping a little bit:

- I figured out why I think this way (nothing was ever good enough to get my mother's attention) so whenever I realize what I'm doing, I remind myself that it's my mother's fault and I use my anger about it to help change the focus of my thinking. If/when that doesn't work, I try the childish technique of 'I'm going to get back at her by doing the opposite!' (Yes, I'm aware that blaming others and acting like a child are wrong but if it has a positive and motivating effect then I'm okay with it.)
- I try to remember where upholding the impossibly high standards for myself got me. (I landed in the hospital from a break down that followed several months of averaging 3 hours of sleep per night, eating only 2 meals per day, and running myself ragged with work even on Saturday nights.) As I never want that to happen again, I keep trying to remind myself that if I don't lower my expectations (at least a little bit) then I will end up in that position again.
- I try to convince myself -- and epically fail -- that if I don't have any expectations, or at least signifucantly lower than my current ones, then I don't have to go through the misery of the disappointment that inevitably follows with failing at my current expectations.

There was one thing I did at work at helped but it doesn't exactly apply well.... I've always been one to put others first and help out wherever I can; however, I've realized that if I don't cut off help toward people who are lazy and/or are just going to take advantage of me then I definitely won't have time to meet my overwhelmingly high self standards. It was almost like giving up on them but if I didn't, it was just giving me a crap-ton of extra work to do and eating jnto the limited time I already had to complete my work. It helped quite a bit so I got to accomplish more than usual but it had no effect on my coping skills for the high standards.

Hopefully these ideas can semi-help someone.