Stop on holidays. Take champix. An cut alcohol and coffee for a few days and that'all you have to do quit.
That's terrible advice. Champix and Zyban produce "feelings of agitation, depressed mood, hostility, changes in behaviour or impulsive or disturbing thoughts, such as ideas of self-harm or of harming others". I had several doctors literally tell me "to stay the fuck away from that garbage"
My family is deeply grateful for that "garbage".