I've been there. It's been years since I smoked a cigarette, and I am very confident that I never will again. Let me tell you how I quit...
I could not quit cold turkey. Some people have, and that's great for them. First I stopped making excuses. I tried to picture in my mind Christ smoking, and I just couldn't do it. Then I tried to picture me lighting a cigarette right in front of God's throne, couldn't do that either. This was not Christ-like, and something that I no longer wanted in my life. And there was no excuse for me to replace one sin with another, so I didn't eat just because I wanted a cigarette. Going to God in prayer is where I needed to seek comfort. But I twirled my hair or took up knitting to replace the physical habit of doing something with my hands.
As for the actual nicotine addiction, I set a timer. I started with one minute- when I had my next craving I had to wait sixty seconds before I could have a cigarette. For every new craving I had to double that waiting time. So one minute turned into two minutes, then four minutes, then eight minutes. Eventually I got up to hours and days. There were times that by the time the timer went off I no longer had the craving, and got busy with something else, so I didn't smoke. Eventually I weaned myself off. And I'm still smoke free years later. I like breathing in deep and feeling my lungs are satisfied. When I see people smoke on tv it disgusts me. I remember the awful taste, the shortness of breath, the stinky smell, the expense. I just don't want it anymore.