I was hard smoker for 15+ years and manage to quit cold turkey without any problems at all. Like next day I was sitting and wonder why I don't need a cigarette. Not only I quit smoking, but coffe as well, same day (I associate coffee with cigarettes so was pointless to continue drinking coffee)
How it happened:
A friend of mine told me that I am like low life junky, that I prefer to spend money on tobacco instead of food (money was really short back then) etc - it get me so pissed (mostly because was true) that I said to myself (and her) "Who is junky? Me? Tomorrow ill be no longer smoking". For my uber surprise next day I had no desire at all to smoke. Now how the fuck this happened? I tried quiting a million times and never worked, now I was scratching my head why I don't need to smoke.
What I found out (by this personal experience) that decisions you make when you are in high emotional distress tend to get "imprinted" in your brain and sticks. So I test it with other stuff and it worked for me, every time. What I did it start imagining situations that I know will pump my adrenaline sky high and get me pissed as hell and then says to myself "I no longer do this", "I no longer care about her" (no shit I heal a broken hearth this way), right before going to bed. Sleep over it and next day you are new person. Oh and brush your teeth immediately after you eat. Toothpaste remove the need to smoke after eating.
Now thats my story, and thats what worked for me. Go, try it, you have nothing to lose.