I was a heavy smoker for over 30 years. I quit cigarettes after 3 days of vaping, I just didn't like the taste of cigarettes anymore. At that time I would buy cigarettes by the carton and I had two packs left when I quit. I left those two packs sit on my desk for over a year just to see if I would be tempted and I never was. Haven't had, or wanted a cigarette since 3/14/11.
As far as running out of vape material, I've gotten into the habit of carrying a small case around with me with spare batteries, filled tanks and even a backup 808 with a couple of cartos. When I started, everything I used was pretty much mail order, so I'd buy about a months worth of supplies at a time. (I guess being an engineer I plan for worst case scenarios)
Now a brick and mortar vaping store carrying a wide selection of products has opened up about 3 miles from my home so I don't worry as much about having to anticipate needing, say, atomizers at least a week in advance. It's also nice that they have a system in the store for allowing customers to sample juice a few puffs at a time (pre-filled tanks with disposable mouthpieces that slip over the tank mouthpiece).