I just wanted to say good for you to go back and give him a blanket. Being kind is sometimes the only point.
Yes he got drunk on his own, yes he is messed up, yes he is making bad choices.
I feel like anyone who does not have that kind of life and doesn't have the issues that cause that life should be grateful everyday. Grateful and compassionate. Even when, maybe especially when, the circumstances some from within.
Believe me, I'm not always able to be kind when someone harasses me or when I think "You're as healthy as me! Stop asking me for money and get off of your butt" but if they were as healthy as people that don't have that kind of life -they wouldn't have that kind of life.
There are a lot of ways to be unhealthy and some cause people to make bad choices.
I don't know the answer and I am not immune to the frustration and it's hard sometimes to remember how lucky I am.