Why do I keep outliving my friends and everyone I care about?

Lost my oldest friend tonight out of the blue. His wife called me which I thought was odd at first because she never calls me. I picked up and she told me he died. No idea about the actual cause yet but she said he suddenly had trouble breathing and he went to the other room to use his nebulizer because he has asthma and usually that helps. His wife went back to check on him and he was turning blue. Ambulance came and he didn't make it.

I have lost so many friends in my lifetime yet I'm still here. I don't understand. If anyone should have died it's me. I'm the drug addict who has struggled off and on for decades. I'm the problem child yet everyone else dies and I'm still around. How is that fair. I've known him since we were 7 years old. He was my first friend when I moved to town and we went through so much together. I can't wrap my head around it.