Are drug-alcohol addictions a diagnosed mental illness? is it a way of life that may involve disorders?

Both and more: Your question can take a book to answer, but simply: yes, even in the newest dsm, it is a diagnosis. Also, as you note - it is a way of life that (at the extreme of addiction) certainly involves disorders. Last i heard, 12-step programs were still the most successful way to deal with addictions of all types. Good luck!

Addiction+ diagnosis: Addiction to substances of all kinds are listed in a section of the diagnostic & statistical manual (dsm). However, addictions to alcohol and other drugs are actually a metabolic disorder wherein the brain does not process alcohol or other mood altering substances in a normal way.