Creative work is often driven by pain. It may be that if you don’t have something in the back of your head driving you nuts, you may not do anything. It’s not a good arrangement. If I were God, I wouldn’t have done it that way. Things I’ve written about are no longer of any interest to me, but they were certainly of interest before I wrote about them. So there’s something about writing about it that flattens them. You’ve used them up.
I suppose this is kind of a roundabout way of saying that writing about painful stuff can be therapeutic and helpful, although his way of saying it is much more awesome and writerly. I love the image of “flattening” things by getting them into writing. Although maybe you have to be a genius like Cormac McCarthy to really flatten things effectively. The way I write, I’m probably just plumping things up.