I'll add that I quit about 17 years ago. Yes, life sucked for about three months as I adjusted to life without nicotine. That was a short three months of my life and any discomfort I felt has been mostly forgotten....water under the bridge. The worst was over in about three days. Cyclist are probably better prepared to quit smoking than most. We willingly sign up for suffering when we get on the bike. Nicotine withdrawal is a lot like climbing a hill or a persistent head wind. It's a constant nagging thing that is unrelenting at the time. However, like cresting a hill or finally turning a headwind into a tailwind, the withdrawal does subside and then all that suffering turns to bliss.