You gave him all that you could.
I have a friend who lost a parrot after many years and he took it extremely hard. He also thought the parrot would out- live him. He had designated my brother to take care of him if that is the way things went.
You may know that there are many pet loss support groups. I went to one when one of my cats died in 2011. I couldn't get past the bleak reality that she just wasn't there. I never even posted on the site (in fairness, I know I should have). I read stories from people who were consumed with grief or feeling some kind of guilt. Besides missing her , I wondered if I had her put to sleep too soon--breast cancer that had gone to her lungs. My vet, who had come to my home so kitty could be euthanized on her bed, kept re-assuring me I had done the right thing. You often feel guilt no matter what you do. My kitty's absence was deafening. She was very active and kind of supervised household chores and greeted people at the door and told them what chair they should sit in . LOL
Anyway, the best sites are pet loss support Forums--the "Forum" part being very important if you google. Good ones are Grief Healing Discussion Group, Rainbow Bridge, Lightning Strikes. There is much talk of dogs and cats, but any talk of a beloved pet/child are welcome. All you may need to do is browse and read and you will not feel alone.