Beth,
I am so very, very sorry to hear about the tragic loss of your son. Watching his suffering (and the others) must have been horrible and taken nearly everything out of you. I hope that during this time you have a supportive family around you and reached out to friends who could help.
There is an element of perspective that comes into play when devastating things come into our lives. Your inability to care for your animals came from the focus you had on your tragedy, and trying to save your son's life IMHO.
It took a TON of courage to post this information, and I feel certain that you have gained some of that courage from coming through a tremendous amount of misfortune.
You are a human being. You suffered a tremendous loss, and there were other casualties because of this. You are not a bad person, and don't allow anyone to convince you of that. You now have some sad finality in some matters, but your animals are still with you, and it sounds like there may be time to give them the attention they deserve.
I extend my hand and my heart to you...