Quitting smoking is a great opportunity to learn about ourselves, as you have already observed.
Congratulate yourself on having the desire to stop - then you are over the worst, but still need to maintain your resolve. It's just so easy to start thinking that just one won't hurt, but it does. Just one achieves nothing except feeling the need for another. Whatever you do, don't have just one. Beware - alcohol will weaken your resolve.
Here's a few home-brewed tips that might be useful.
It's not just nicotine addiction - there are 50+ chemicals in cigarettes. Also the main problem is habit.
We have been used to having body sensations which we translate as 'my body needs something', which we have attempted to satisfy by having a cigarette.
When we try to stop smoking, we still get these 'my body needs something' sensations, and we still feel that we want a cigarette. We have to train our body to be more selective. When we feel we need something, we have to work out what it is that we actually need.
A glass of water is an excellent substitute if nothing else comes to mind, as it helps with the clearance of the toxic substances in our body. Another good substitute is a bag of salted peanuts, used in combination with the water.
Another thing to do is to find an activity which occupies the mind or body. Go swimming - nobody wants to smoke while they are swimming. Slowly, as our body adjusts and translates the 'want something' feelings into something other than cigarettes, then the feelings begin to go away. We know its not a cigarette that the body really needs, because as soon as we've had one we still have the feeling, and want another!
We will have a few bouts of feeling or even being short tempered. We must try to bite our lip, and control; ourselves. Recognise the short temper as being the removal of toxins which are trying to find a way out. They went in through the mouth, and they try to get out that way to. We must learn to keep our mouth closed, and force the toxins out the other way.
After we have stopped for a while we will begin to feel that just one wont to any harm.
All that leads to is a desire for just another one. We must guard very strongly against the desire to have just one.