YOU DO NOT HAVE TO UNDERGO ADDICTION to be an effective support for someone struggling.
Your one example makes a difference. Choose not to use, and communicate why.
Check out this article from Psychology Today. We are especially tuned in to #5, Self-Medication
The self-medication theory of addiction suggests that suffering is at the heart of addictive disorders (Khantzian, 2012). That is, individuals with deficits in emotion-regulation skills (i.e., skills relevant for modifying emotional reactions and tolerance for negative emotions) use drugs in an attempt to manage negative or distressing affective states. Alcohol is frequently used as a way of coping with social anxiety.
The drinking removes, at least temporarily, the stress of anxiety, Mate (2010) suggests that addictive behaviors ultimately driven by our unwillingness to allow ourselves to really feel and experience pain, frustration, fear, and all the negative emotions that are part of being human.
Instead, we choose the chemical shortcut to avoid those emotions and become trapped there.