Yeap, it's happened to me. I quit for 3 years, I used to dream about it and feel guilty when I woke up. Then I had this room mate and it started one puff at a time, then one smoke, then a pack a week and so on............
I quit again, but three years later at a time of stress I started again, then quit. This happened one more time. Now I don't have that first drag. I tell myself it will taste terrible and just don't go there! So far so good 1 1/2years fresh and clean!
Good luck fellow slaves!
Cheers Norm