Anyone who abuses alcohol long enough or heavily enough eventually will have problems with memory. The functioning alcoholic will have memory problems. His memory problems are simply less severe than those of the skid-row alcoholic.
As with other toxins excessive use of alcohol destroys brain cells. If the alcohol abuse goes on long enough, eventually it may show up in deteriorating memory, particularly short-term memory.
The first short-term memory problems usually show up long before the drinker begins to have alcoholic blackouts.
Alcoholic blackouts may be an indication that the brain damage is getting more severe. As his alcoholism progresses, the alcoholic will eventually begin to notice gaps in his memory. He cannot remember how he got home last night. He may not remember even where he was drinking last night, or who he was with. This does not mean that he was not aware of what he was doing; he was perfectly aware at the time, but he just can’t remember.
I have often characterized self-medication with alcohol as voluntary dissociation. The functioning alcoholic drinks to split off from the reality of his life, his pain or his feelings of inadequacy. When he enters that altered state he feels better. The problem is that he has become addicted to alcohol over time. Now he simply needs alcohol to feel at all OK.
When people are in dissociated states, with or without alcohol, they are simply not there. So when you tell them something when they are in their altered state, they may not have any recollection of what you told them when they come back to reality. And because they typically don’t realize they were mentally somewhere else, they get defensive and often angry. They may accuse you of lying or holding things from them.
Whether the deteriorating memory in the functional alcoholic is the result of brain damage or dissociation or, more probably, both, it should be taken as a symptom of advancing alcoholism.
If you are a functioning alcoholic and those around you are complaining about your memory problems, get whatever help you need to break your addiction and stop things from getting worse. Take it from someone who has been there: there is life after booze.
If you are a family member of a functioning alcoholic, do seek help yourself, lest you slip into a debilitating codependency role. Going to an Al-Anon meeting might be a good place to start.