This works for me: When I've had enough of something invading my mental space, I practice its destruction. I invite it in mentally and lay in ambush. And then proceed to turn any anger on it and kick it to the curb.

Then, when it appears out of nowhere to ruin my day, I immediately and without mercy show it to the door. It no longer catches me off guard. Eventually, it just gives up and goes away.

The beauty of it is that you don't have to understand one thing about it except that it's harmful and you want to get rid of it. No psychoanalysis necessary.