I was on the nicotine patches when I quit, which helped a lot. But w/o the motivation nothing would have helped. I'm sure I would have died of emphysema years ago if I hadn't quit. Aside from wanting to be able to breathe, another motivation for me was all the times I couldn't enjoy myself because I was in a place where I couldn't smoke - someone's home, a museum, a cinema, a classroom, a long wedding or funeral, etc etc...Also I quit with the attitude that failure is not an option. Besides I didn't want to fail and go through that hell again! If you don't get rid of all the smoking related stuff - ashtrays, lighters, cig cases, etc then you are allowing/expecting to fail. I dumped all of it.
As for second hand smoke... I worked with a woman who didn't smoke and her husband did. They had 4 small kids and he refused to go outside the house to smoke. The wife got lung cancer and died at the age of 33. I've no idea what the health of the kids is now but wouldn't be surprised at asthma or worse. (they live with the grandparents neither of whom smoke).