By my definition and lived experience, addiction is a form of chemically induced mental illness.
Adding alcohol and drugs to pre-existing conditions at the very least hobbles progress.
Substitute the word Addiction for Mental Illness in the pictured quote gives you "The term Addiction shames people, perpetuates stigma and prevents people from getting help."
Innumerable examples of mental illness and addiction, separately and/or together, could (and do) fill volumes.
Find yourself and others you may know within the pages of my first book, ALL DRINKING ASIDE.