Alcoholics experience the alcohol differently from non-alcoholics. The non-alcoholic experiences primarily a sedative and disinhibitory effect.
For achoholics like me, the alcohol is processed by the liver more quickly, it turns into something called acetyladehyde, which manages to travel to the brain where it turns into something called THiQ (tetra hydra iso quoline), which as it turns out is much like morphene. This gives alcholics a different and far more addictive experience.
That powerful feeling we have after the first 2 drinks is (I think) the THiQ build-up in our brains. "Normals"don'texperiences this, and are more able to turn off the switch after a couple. I know that I am not able to do that.