Everyone who has ever taken a drink has chosen to do so, and we usually drink because we like taste and/or the effect alcohol produces. There is nothing harmful or wrong with that slight dopamine surge, at least initially.
A person genetically predisposed to addiction, however, experiences the surge, and that pleasurable sensation gets locked in by other areas and structures of the brain in ways that do not occur in a non-addict. The misguided power of the midbrain surges through the entire pleasure circuitry of the brain and alcohol becomes the dominant drive.
For the alcoholic this experience is overwhelming and sometimes terrifying.
His brain has become wired for alcohol. It has built a pleasure construct around the use of alcohol. The prefrontal cortex has engraved sights, sounds, and smells into this warped alcoholic pleasure construct. A party or ball game becomes a trigger to drink. A type of music becomes a trigger to drink. A smell, such as cigar smoke or even a barbecue become a trigger to drink. Certain people become triggers to drink.
This is an unconscious brain drive that takes over the life of the alcoholic.
What began as a disorder of pleasure ends in a catastrophically impaired ability to choose. Note which came first. The tragically bad choices are the result of underlying brain dysfunctions. The brain is diseased, broken, at some very fundamental levels. Addiction has wrecked the freedom of choice.