Truthfully Brian – it sounds more like you are disgusted with your friend, than compassionate.
I’ve seen drug and alcohol addiction up close (immediate family). Until the person admits they have ANY problem, they’re not going to change. In order to convince them they have a problem you’d better at least pretend to care.
Also, there are often root problems that need addressing in order to deal with addiction. In my family member’s case there were two root causes – pain from a long forgotten bone break – that was being self medicated. (Ankle hurts, so lets have a scotch to make it hurt less.) And being in a miserable marriage with no good way out… Surgery helped alleviate the pain and self medication – and re-engaging in the marriage helped the emotional problems. Once those causes were mitigated, the person was willing to admit a problem and start cutting back. But even then years of abuse/habit/craving were hard to undo. It’s not an easy addiction to stop.
Will power works great in avoiding the start of addiction, but not so much when the physical addiction is there.