This worked for me, too.
I started smoking at a very young age and smoked heavily all through college. When I graduated, I decided it was time to change. No smoking in my practical new "grown up" car, and no smoking at my new "grown up" job. These two decisions drastically reduced the number of cigarettes I was used to smoking each day. Soon thereafter I stopped smoking in the evenings after work, and only smoked when out for drinks with friends during weekends. In time, I was able to give that up as well (I found that I felt much worse the morning after a night out on the town when I had smoked a few cigarettes than when I had abstained).
I can't remember the last time I smoked a cigarette at this point. I never said to myself, "this is it, this is the last one." I just cut down, and then then stopped altogether. For a long time I missed the act of smoking, even after the physical urges were no longer there. It was such a part of my daily routine for so long. I don't want to live forever, but I don't want to be carrying around an oxygen tank (or worse) in my old age either. If you can't do it for yourself, do it for your family and friends.
If cigarettes were not quite so harmful (and expensive), I would never been seen without one in my mouth. Unfortunately, that's not the case!