We had a 2 yo jack russell, got very sick, vet did a great job, but the man upstairs took him in his sleep. I'm glad at that point we didn't have to make "that" decision, as I know I wouldn't have taken it well. We buried the little man in our back yard (as Kerrie posted about).
This time, with our older dog, this particular decision was going through my mind in the last week, as he kept peeing everywhere. Was just so scared to take to the vet, knowing full well it might be the last time.
Managed to grab the courage to take him (a week later), only to find we picked up an early onset of diabetes. OMG, worked myself up so much thinking it was the end of it, and it was diabetes.
He is fine now. And so are we.
But the pain of this decision, man I pat you on the back for doing what you had to do.
I have been through the Human kind of this, in the worst possible way (grandfather was basically brain dead and legally had to starve him to death, as by the letter of the law, which of course is total BS).
I could not put a pet through this, let alone myself or anyone ever again.
Let me tell you, you did the right thing.