"Neuroplasticity and epigenetics" are the new theory of alcoholism and addiction that I learned here at SR.
"Should quitting alcohol be so different from quitting smoking?" My answer answer is yes, they are very different chemicals, possibly affecting different parts of the brain. Alcoholism seems to impair that part of the brain which is most highly evolved in humans--that part of the brain which controls our social functioning. Thus, a social setting is the most effective cure. That's why we need to keep going to meetings.