Absolutely not! Alcohol and/or drugs are never a substitution for medications. Alcohol is a depressant drug itself and leads to more depression. Marijuana causes people to be apathetic, unmotivated, and depressed as well. Additionally people often lose their inhibitions when abusing alcohol and many suicide attempts happen while people are intoxicated, so for this young man it increases the chances he will attempt suicide again. Personality changes can also happen with substance abuse. It is very possible that the majority of changes you have seen in the last 6 months are related to substance abuse. We would not know until he remains clean and sober for a good period of time to see if those symptoms go away. If not, then he is likely experiencing a depressive episode.
I would certainly hope a counselor would not say this. Is it maybe the mother's misinterpretation of what the counselor said? The counselor might have said something like "the young man is self-medicating". What that means is someone is trying to escape their psychiatric symptoms through substance abuse, but it should be stressed very clearly, this is not an effective treatment for depression or any mental illness.
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