Batshit insane by most accounts, Babe. And he wasn't exactly the picture of mental health himself. They were both seriously depressed and chronic alcoholics. But he was as much of a genius as he was crazy. I've read everything he ever published at least twice. I've probably read "Gatsby" a dozen times.
"I got news for you. If it wasn't for the toilet, there would be no books." --- George Costanza.