I lost my Mother and my Father to Smoking. Maybe that is why I never started. In those days I can still remember gasping for air in the back seat of the car while they both puffed away. Nobody really knew any better back then. My ol man was only 59 when he died of lung cancer, my mom made it to 72 if you weant to count two years of lugging oxygen. Bottom line is you will quit sooner or later, lets hope sooner. Like many here have said, only when you really want to you will. I can tell you both my parents told me they regretted not stopping. Too bad it was too late to see their grandchildren grow. I heard a quote once that makes a lot of sense. Maybe it will help you or maybe even others trying to accomplish something. I do not remember the author. Basically saying, don't go into anything with the attitude of trying, go into it with the attitude of doing. No trying.
"Do or do not, but do not try".
Good luck Brother.