I have been mind coaching two olympic springboard divers and what struck me was the similarity between there dedication and courage and quit smoking. The divers have made up their minds, set their goals and focused entirely on going to the olympics and competing for a medal. As with quit smoking you need to make up your mind to quit, set the goal to quit and put all of your focus and effort into quitting. With the divers quitting was not an option but with someone who wants to quit smoking quitting is the only option.
Get into this mindset and there will be nothing that will prevent you from becoming a permanent non-smoker that breathes fresh air for the rest of their long healthy life.