Attention is a resource. You have limited amount of it. When an event passes into your life, decide if it’s worth your time to worry about it. Ask yourself along the line of these questions:
Is this that important? Should I really spend time on it?
Someone said a bad thing about me. Should I care about that?
Do I want to do this? What good will come out of it?
Why should I give a fuck?
You can only focus on one thing at a time. By taking in new things to care about, you sacrifice time that could be spent on other projects already under your responsibilities. By worrying about stupid things, you forget to use your mind for other more productive and more worthwhile issues.
Your mental resource is limited. Choose wisely how to use it.