I wish I had the right words to comfort you Jim, and I'm sorry for the many losses in your life. I can't imagine what it's like to lose siblings and children.
At the club where I attend AA meetings, it seems like we lose a few people every month. A few of them pass on quietly, sober after many years of recovery. Sadly, many of them are not so fortunate, addictions are not pretty diseases to die from. In my 45 years on this earth, I've watched my mother die from drinking and smoking, had a friend die in a murder-suicide, had another friend get drunk and drown in a canal, and in the last 4 years I've been sober I've watched quite a few others go, victims of substances.
Sometimes I can accept that one must die so that many can be saved, other times I just can't comprehend why God chooses certain people.
I've found the "Serenity Now!" search function at this site
Hazelden -- Thought for the Day very helpful for meditations to help me through difficult periods in my life. The words
hurt, confused, angry brought up dozens of meditations, maybe you'd find some of them useful.