How old was your brother when he died?
I ask because I have a daughter who will be 48 tomorrow and she has been in and out of addiction for 28 years. I always fear I will get the call that she is gone, come to the morgue. It breaks the whole family's hearts but also messes up parts of their life, and makes them angry too. She lives in a rehab facility right now but it's been a struggle since last Christmas. I have been writing about her if you get the chance to read some.
I support you in your sadness and grief. He was your brother and, as you said, you once looked up to him. It cannot be easy to lose him like that.