I had a buddy of mine that died earlier this year from cancer. He'd pretty much done it all, really big on pills but he'd told me several years ago that there was NO comparison, that cigarettes was something he had tried over & over & over to quit to no avail & before he died he was on oxygen for awhile & he would actually take a hit off the oxygen machine & then take a puff off of a cigarette! He even had it blow up in his face (wasn't real bad but did leave a few burns on his nose & face) we tried to tell him that could happen but he was at that point that it just didn't matter, he HAD to have that smoke!

I'm sorry about your friend. IMO, the psychological addiction is MUCH tougher to kick than the physical addiction, and believe that applies to all substances. If one is physically addicted, Alcohol is the ONLY one that can kill you if you go cold turkey, not cigs, nor any of the opiates. I've seen a few withdrawals from opiates (no difference between Morphine, Oxy, Herion, etc.) as family members were hooked (cancer treatment) then "cut off" when the C regressed. I've also seen folks hospitalized with NO SMOKES for several weeks (past the physical withdrawal of nicotine), and the first damn thing they do is light one up when they get a chance. I've always said: Quitin' is the easy part...not starting back is the REAL issue for most (regardless of the substance). Addicts are prone to be addicts...the substance might change, but the "addictive personality" doesn't...YMMV.

Addictions are what creates endorphins: Habits which the mind trains itself to "heal itself" and feel better temporarily or long-term.
That isn't always correct or beneficial.

Drugs, excercize, religion, art, work, fixing what's wrong, communication, whatever.
If we didn't have have OCD addicted mathematicians and coders we wouldn't have computers....