Rule number one is, don't sweat the small stuff. Rule number two is, it's all small stuff.
It's important to run not on the fast track, but on your track. Pretend that you have only six months to live, and make three lists: the things you have to do, want to do, and neither have to do nor want to do. Then, for the rest of your life, forget everything on the third list.
If you can't fight and you can't flee, flow.