Hey G, you ok? I know you want answers, believe me. But it doesnt really matter why at this point.
He is lost, confused and depressed. He is not living in reality. Well, he sure as hell just got a huge plate of reality now.
Just remember that this is not your fault, nor your burden. At all. You did your best, tried your hardest, but I believe everything happens for a reason. It is best to trust that God knows what it is. Leave it to Him.
I know that you are making some decisions. If you can, sit with them just a little bit. Then, if you really feel they are right, follow them through.
You are going to go through a lot of emotions - shock, denial, anger, and sadness. Allow yourself to go through each one. And then after you have, you will come to accept what has happened. And I dont mean accept this child, I mean accept that there was nothing you could do. These steps are all necessary. Dont rush them.
Sweetie, it all seems more than you can take. But you will be ok again. I know it. You have such strength - more than you realize and such grace.
Give it all to God, Peace for He will get you through.
I am on the alt if you ever want to talk. Same name as here.