I've gotta chime in here and retell the method my older brother used to quit. He was your typical Hicksian two-lighters-a-day smoker. I don't know if he just made this up or got the idea from someone else or what, but it seemed to work. And it sure sounds like it would work.
The Method is: Take a Mason jar/canning jar/mayonaise jar with some tight cap. Clean it if it's dirty. Put in, I dunno, a half-cup/cup of water. Then place an assortment of cigarette butts. Shake. Let it mature for a day or two.
Any time you get the urge to have a cigarette, carefully open the jar and take a wiff.
That urge will be short lived.