This person could be experiencing problems in other areas of their life. This is typical of a functional alcoholic or drug addict. The fact is that this disease is progressive. It will eventually lead to deterioration of every aspect of a person's life. Since not every human being is the same, we can assume that their drinking and drugging patterns are also not the same.
Some people drink or drug periodically while others binge.
The fact is that an alcoholic or addict will continue to experience more severe consequences through time. Family members will see changes in their love one's social, psychological, physical and spiritual aspects of their life. The fact is that the addict will not be able to drink or drug normally. They will not be able to recover by themselves. We love them too much to see them destroy themselves and our families.