I meant the cognitive change, not necessarily the emotional change it may bring about. I, too, have been in extremely depressed stages, and I know the whole "Well, do I really want to be happy again?" dilemma. That's when my chronic pain began, and over time, I realized I was making myself hurt more with the misery and self-pity I was afflicting on myself. That's when I discovered pot, and it showed me that I can live life with pain.

EDIT: Funny thing you're on tonight, Gandalf, I'm watching my copy of 1978's Lord of the Rings by Ralph Bakshi... Good stuff