My late wife tried quitting two times before she succeeded on her third try, with an American Lung Association group that provided support and a few methods. Most memorably, she smoked only in one place in the house, and kept a tall Mason jar with all the butts to dramatize the amount she was smoking.
It was dramatic enough, and visual enough, to break her of a three pack a day or more habit that was closely associated with her grading papers and writing. It wasn't easy, and it wasn't fun, but it kept her spirits up and provided enough competitive edge so she stayed with the process.
I quit my pipe in solidarity, knowing how important it was to her health and energy level. Her final illness was not smoking related as far as the science knows. And she felt a lot better after quitting, and regained her ability to walk distances and stopped clouding the windows above her paper grading station with cigarette tar.
I blew up when a guest at a New Years party we gave tempted her with cigarettes. What a jerk. I wasn't sorry I'd been rude about it. How bloody cruel. But that's a different story. If people want to quit, support them, never mind your own addictions.