Mstrust
Your story touches me in so many ways. There isn't much I can say to ease your pain, because the pain of losing someone is equal to the love you bore. But I wish you all the support you need as you grieve.
Addiction is a disease - and I am so sorry it claimed the life of your loved one. Even when we lose someone to cancer or heart disease, there is always a temptation to torture ourselves with second guessing about what we could have done, could have said.
My hope for you is that you can acknowledge that you did absolutely everything correctly. Each decision and action you took was perfect for the moment you made it - and your HP gave you those beautiful last 36 hours where both you and your ABF could feel the love that was beyond the disease.
Wishing you peace as you grieve because he is at peace now.