I've tried to stop smoking pot so many times over the last 8-9 years. It never works though, I make it through maybe a couple months at most and then go back to smoking because I can't find anything else to do with myself. I feel empty and without pleasure without them, and even trying to keep myself busy like others suggest does nothing for me. It kind of sucks because when I smoke my short term memory is shit, making learning and retaining info difficult. But there's just nothing else that keeps me occupied enough to not have this sinking feeling, not nearly as much as just getting stoned and hazy enough to not think at all.