My mom has Alzheimer's and we all wish they would give her a shot to end the suffering. Its no way to live. We would all gladly take the shot if we were like that. But you have to go to Oregon to do that.I have had to put a dog or two down. It is terrible. Like losing one of the family. I am sorry for our loss, but don't blame yourself. You did the right thing.
You gave the dog a great life and ended it's suffering. Lucky dog.