For those trying to quit, here is what I learned at a quit smoking class. It was long after I was freed from it, but my husband was too ill to go, I went for him and took notes.
Nicotine is the perfect tranquilizer for some minutes, then it becomes a poison with the only antidote more nicotine. The results of the poison is that it creates nervousness and tension. The antidote then is more nicotine.
Nicotine masquerades as the best friend you could have, there any time you call. You only remember the feeling of contentment and pleasure from the first minutes, not realizing the tension that comes after the first few minutes are also directly from the nicotine. The few minutes of pleasure it gives is like someone giving you candy so you get close enough they can stab you. You should give yourself about three days to a week to say goodbye to them. Each day, smoke less and less, always remembering you are preparing for a final parting from them.
When the day of parting comes, get rid of all of them. Prepare for the worst that nicotine has done to your nerves. Prepare for the craving for more nicotine to give those few minutes of release and pleasure, but know it is not worth it because the price for those minutes is too high. Tell people around you that you will not be yourself for a week, or long enough to get the nicotine out of your system. Know that all the misery and negative reactions to all things is not you, it is the nicotine working in you, and be sure the people around you know that, too.
Any time you take nicotine in any form after this, you will need more nicotine to offset the need for it your body will have. It just means you will have to go through the process all over again.