Seized By Frustration

We all get frustrated at some point in our lives - it can happen practically any time, anywhere. I find that most of my frustration happens at work. And I have been able to diagnose the root cause of my frustration however, I have not been able to do anything to prevent it in the future.

I get frustrated at work when co-workers don't perform at an above average level - I feel like there are those that 'just get by' with what they can and would not think twice about going above and beyond their usual tasks.
There are times when I get frustrated when the system runs like crap and developers can't explain why - but tell you that it's not happening to them. Ummm- that's not the point...it's happening, do something about it.
There is one person (in a sea of many) that frustrates me any time I hear his voice, see his name or get an email from him - because he just doesn't do his job - plain and simple. He's been with the group longer than I have, yet he doesn't seem to be able to answer simple questions....afterall, he's production support...it's his job to answer simple questions...but instead, he sends an email to me or someone else from my team to answer the question for him - and then he just copies and pastes what we've responded to him with and passes it off as his own.

So what is the root cause of my frustrations? Stupid people. But it goes beyond people being stupid, because there are stupid people everywhere.
I have realized that my expectations are too high.
I have always received glowing reviews from my higher ups. I perform my tasks and many things beyond my job scope. I train new people that come onto the team and I try to help them as they begin to learn the ropes.
Fast forward two months - I am now repeating the things that I said to the new person a week ago. We keep talking about the same thing every week cause you can't seem to grasp the concept; yet you never ask questions.

Yes, folks, it's me. I have set my standards at, supposedly, an unattainable level. When someone older, with the same industry experience comes in, I feel like they should catch on rather quickly and hold to a certain professionalism. But apparently that's too much. It's too much to ask for a new person to show up to work by 9 am and be on time for 9:30 meetings. Shame on me for being upset with new person for showing up to two out of three 9:30 meetings 10-20 minutes late because she either 1) went to the cafeteria to get breakfast or 2) just wasn't in the office at 9:30 am.

So how does one work on this? How does one take a 'who cares' attitude? How do you keep emotion out of the workplace? That has always seemed to be my downfall.