I started smoking because I wanted to be cool and also I wanted to die.
I started smoking cigarettes when I was 17 going on 18. My friend left a pack of Marlboro Lights (ew!) at my house. I had never understood how to properly inhale before then, but it suddenly clicked. I made a one-a-day rule for myself. When the pack ran out, I bought another. It was the summer after my graduation from ASP, the American School of Paris. After a few weeks my one-a-day rule went out the window like the thousands of butts I have jettisoned.
When I got to UMBC to start my freshman year, there was an awkward refractory period between my arrival and my 18th birthday, meaning I could not legally buy cigarettes. Luckily, there were plenty of people willing to help me out. I had always been very asocial, a huge loser at both the high schools I attended, but being in college, coupled with my new habit (and a few other new habits), allowed me to move past the social barriers in my way. To have a cigarette with a friend is a pure joy, to be sure. To bum a cigarette off a stranger or ask for a light is the easiest way to talk to someone else. I revelled in it.
It’s so passe to smoke in the 21st century. Everyone knows how bad they kill you, and the high priority placed on smelling good and being in good health makes smoking actually disgusting to much of the population. UMaryland placed a system-wide ban on smoking on campus once my freshman year was over, and I now must be corralled into a plastic box with the vaping neckbeards and too-friendly boys in basketball shorts – that, or hide in the forest or under the stairs. There is no glamour, and the social factor is pretty much gone.
What is maybe the most ironic is that I don’t even want to die any more! Now I just damage my lungs because I have to.
Unruly Bodies 
Can I just say that the opening to this post seems sounds perfect as an opening to some amazing coming-of-age novel? You excelled at grasping attention with this one, which I guess helps support the social theory of smoking you discuss in this post. I am not a cigarette smoker, but I surround myself with people who have been or still are smokers, and their stories seem very similar to your own experience. A friend of mine has been on and off quitting for a long time now; she can go a long time without smoking, but she is also really into the raver scene, and the second one of her friends lights up as a show, she joins in almost unconsciously. The social aspect of smoking helps bring people in, and the dependence brings people back, but for some I see it being more social than others. So yeah, this is a great post, and it’s good to know you don’t want to die anymore!