From Very Recent History:

The thing about not thinking about a bad thing was that when you tried not to think about it, then all you could do was think about it, until, finally, the brain slipped, and then you succeeded, you actually didn’t think about it anymore, except that didn’t last forever. Then a moment would come when you’d sit up in bed in a horror in the dark, and you couldn’t help but think about it. But then you’d try to comfort yourself back to sleep, and then you’d forget again.