Watching someone slowly kill themselves is like watching someone slowly die. Yes, you have the choice to not watch... but it still hurts to think about it.
It might hurt worse that they are the reason they are dying and not an incurable disease.
I'm sorry you had cancer, but obviously cancer and addiction are two different things or else they wouldn't be named two different things.
If your watching someone slowly die (be it there fault or not)... it still hurts like hell.
I agree that addiction is totally different but grieving for a loved one... is not. We may have to agree to disagree on this one.