I work with disadvantaged youth. There are some things I find are particularly helpful in their lives.
You can stop being angry about something that happens and that doesn't mean that the thing that happened wasn't wrong.
Thinking errors cause cognitive dissonance. Cognitive dissonance is a fancy way of describing the feeling we have when things suck. They are only called 'errors' because they cause dissonance - literally when we encounter things different then the way we feel they should be.
These include such things as:
The belief life should be fair.
The belief that wicked people should be punished.
The belief that people should treat us with respect.
The belief that parents should love their children.
These things are certainly desirable, but clearly there are many situations where they are not the case. Life isn't fair. Wicked people get away with stuff all the time. People don't treat us with respect, and parents often don't love their children.
You don't have control over anything but what thoughts and actions you choose to take. You can't control other people, you can't control your moods, you can't control your genetics, you can't control anything other than your thoughts and choices.
Making positive choices and thinking correctly can certainly influence those things, but at the end of the day, all we have control over are our thoughts.