In order to quit and to stay quit I would have to say it is completely a mental battle. To get through the first few months after I quit and when cravings were at the worst, I had to keep telling my subconscious mind about all the things I would enjoy more as a non smoker. Like the smell of air itself after a spring rain or the smell of mowed hay. Taste is enhanced and all the foods I enjoy I will get to enjoy even more. Smoking really deadens your taste and smell and once you quit you will notice those senses coming back. Sleeping at night without your spouse kicking you to the couch for weezing or waking up in the mornings without hacking up a lung are things to look forward to. Kisses from your sweetie are sweeter and figuring out what you are going to spend that saved cash are all things to tell your mind to look forward to.That indicates to me the addiction is more mental than physical. Some doctors agree, some don't.
I remember the time right after I quit. Reaching for my shirt pocket for a smoke out of habit even though there were no smokes there. The little devil on my shoulder telling me that one smoke wouldn't hurt after pigging out on a great meal...yet knowing that even one cigarette makes we a smoker and not a non smoker. One of the hardest things to do in my life was to give up those smokes, but like I said before...you just got to get bullheaded and view them as the enemy out to destroy great things to come in your life. You CAN do it!