A concept I've always felt to be a really interesting take on "addiction," as it were, is that those of us who consider ourselves alcoholics or addicts have physical and mental allergy to these substances. We react to them in ways that most people simply don't.
I'll give some personal examples from my intrepid adventures with... I'll pick alcohol:
1. Before I stopped, I was the guy who would walk around a party with an entire fifth of liquor for myself, drinking it straight from the bottle as others sipped their beers and socialized. I kept drinking, wouldn't black out, wouldn't throw up, and wouldn't do anything stupid. But I always had to have more, and I invariably woke the next morning ready to drink again. I found that I didn't need a recovery period - drinking more was always an option to me regardless of the time of day, people I was with or situation I was in, and I could always handle it - This is an example of my physical allergy to alcohol.
2. I never really liked alcohol. I didn't like the potential consequences, yes, but even moreso, I simply didn't enjoy the feeling. Yet, determined to alter my state of mind, I continued to consume booze for many years. As I mentioned earlier, it was in every way my paying to feel like shit and being absolutely unable to stop. There's a saying in the 12-step program (sorry to bring the program into it, I'm just giving context) that goes "One is too many and a thousand is never enough." For me, this applied to all drugs, including alcohol: Put one drink in me, and I'm off to the races, living recklessly and in constant states of guilt, shame, selfishness and self-pity. But let me drink to extravagant excesses, and I'll spend the whole experience consumed with anxiety over where I'll get the next one - or, to be more precise, the next several. I never lived in the moment, never "experienced" alcohol as others did, because I had only one thought - WTF do I do when I run out? This is an example of my mental allergy to drugs and alcohol.
I still think this is a very thought-provoking lens through which one might evaluate their own tendencies towards use and abuse of psychoactives.
The difference between this and traditional allergies is this: One who is allergic to peanuts - suffers serious consequences after the consumption of peanut products and will always suffer these consequences - avoids peanut products. It's just a part of life.
Without support and a plan, I will imbibe alcohol and take any number of drugs - suffer serious (and twice fatal) consequences - and then take more. My addiction is "cunning, baffling and powerful" in the strongest sense of each word. Once I realized this (and actually accepted it), the necessity of abstaining from drugs and alcohol by any means necessary became self-evident, and it's really spurred growth in my personal journey to be free of the mental obscurity that accompanies my allergy.
FWIW.
~ vaya