It really is a willpower thing, that's all there is to it.
And if you're having a REALLY bad day, or you're stressed out, (or you're drinking) your willpower turns to crap and you lose grip on it.
The only way I was able to quit was to stop drinking for a few weeks.  Then, I told my friends and girlfriend no matter what, under no circumstances give me a cigarette when I go out, and if I do you can punch me in the face.
That kept me from smoking when I went out.  eventually, you'll *mostly* lose the cravings.  They do come back from time to time, but after a year or so, cigarettes will probably taste like ASS if you try to smoke one (I broke down a year later and had about 2 puffs.  That was the end of that )..
Good luck.  I know how tough it is and commend anyone who is really working at it.