pulmonary rehabilitation

I’m in LA with my mother while my sister is on vacation and floods ravage the Midwest. Twice a week, Mom goes to a pulmonary rehabilitation class. Everybody else in the class appears substantially younger than she and was a heavy smoker. Several have had multiple hospitalizations after which they returned to smoking. I know this is sort of dumb of me, but I never smoked and it was only recently that I realized that the reason smoking is so addictive is that it makes people feel good. Mom never smoked, and her diagnosis is “idiopathic pulmonary fibrosis,” which means they don’t know what caused the scarring in her lungs.