When you start feeling blue because of the absence of nicotine - you must resist. Nicotine stimulates the pleasure centers of the brain, but many other things do too, that are not harmful. Stuff such as sex, kissing, chocolate, lollies, sweet aroma, your favourite food/drink etc all make you feel good and are way better than smoking. If you really feel your mouth tingling for that cigarette and you don't like gum then you can get those special products - they are things that look exactly like cigarettes, then you "smoke" them and instead of smoke it's steam that comes out, but apparently it has a similar sensation in the mouth and helps people who just have the habit of sitting down and having a cigarette. Whatever happens DO NOT reach for cigarettes, resist the urge and you will be proud of what you did. Chuck out all the cigarettes in your house and don't go to places where people smoke and also don't hang out with smokers.
Soon you will quit smoking and be glad that you did! Good luck, wish you the best!