Addictive personality? That sucks. I have one too. I managed to kick the gambling habit, I managed to cut back drastically on drinking, and I managed to be smart enough to stay away from drugs. I still smoke a lot though. My advice: you need to find a reason to quit. Gambling: my finances could not handle it... i stopped. Drinking... can't drink daily and fly freight- so I don't. Smoking... well, I really have no reason to stop (other than the obvious no brainer reasons). I did, however, have an ex-girlfriend who I was in love with tell me either quit or she was out. I stopped... kindof (while we were together I did). She left me and I took it back up. Not the smartest thing I've ever done. I know it's easier said than done... trust me I know... but it has worked for me in the past. I had to go into it with an attitude that i had to quit, not that I should quit. You have no option but to stop for xxx reason.
I hope it works for you! Good luck! Just don't wait for the doctor telling you that you need to quit due to medical reasons (and I need to follow my own advice too).