Originally Posted by
SoberInCLE 
My friend has been a heavy user for the past 20 years and he says that he quit several months ago and now he is depressed.
Sounds very familiar to me. I quit expecting nothing but good times, but over the course of the last two years I have hit lows I'd never hit when I was smoking daily. They didn't last very long, a week and a half max but I've had five of those bouts or so. I've been good since the summer vacation and I'm under the impression that I'm a bit more stable now.
I suggest your friend talks to someone professionally if he think he's depressed.