Excellent post!
I think a lot of folks don't fully understand that spiritual illness (sin) and physical illness are often intertwined. And I think this is especially true when we're talking about a malady like addiction.
Just to use myself as an example, I believe I was born with a genetic predisposition to become alcoholic. But to define exactly how that predisposition manifested in me, I would have to describe what I would call 'spiritual shortcomings'; like an intense self-centeredness that caused me to be always very uncomfortable in my own skin. And an intense ego-centrism that caused me to think and expect far too much of myself, leading to a constant sense of hidden and innate failure. And I know these characteristics are common among addicts and alcoholics. And then add to that the fact that certain euphoria producing chemicals have an especially strong effect on some people, like me, and it makes for a very powerful 1-2 punch in favor of the excessive use of those chemicals once we get access to them. And that's the doorway to an addiction.
I was not born a drunk. But I became one because everything about me, and in me, had set me up to do so. The first time I drank alcohol I thought I'd found a magical elixir that was able to finally relieve me of myself! And all I wanted from that moment on was to drink more of it and all the time. It became my primary quest.
I was 12 years old at the time. Not exactly an age of reason, with the power to deny myself such an intensely euphoric experience based on threats of 'sin' or addiction. And by the time I was old enough to appreciate the validity of those threats, it was too late.
Addiction preys on a distorted sense of self, by relieving it temporarily. But in doing so, over time, it distorts it even further. And this process is biological as well as habitual, and psychological. Sin is a spiritual illness. Obsessive self-destructive behavior is a psychological illness. And chemical addiction/abuse is a physical illness.
Alcohol and drug addictions are comprised of all three. Which is why most addict/alcoholics will die in and of their addiction. As did Robin Williams.