Best help I ever got was from my Doc!
"I will sign you off this time, but if you come back in 6 months, sorry! no medical"
Made up my mind that I don't smoke anymore, hard for about three weeks, but stayed determined. Now I hate the smell, dirty ashtrays, lingering whiff on clothes, smoky breath....yeah I'm a reformed smoker, a real pain in the ass where the weed is concerned.
If you are offered a cigarette, say "I don't smoke", not "oh! I just gave them up" less pressure and makes you feel a little better. Stick at it.