I've had my share of old pets. You may remember Henry. There are many others. He happens to the one about whom I have thus far posted.
If you've grown up and always lived with pets as I have, you understand the experience of having an old pet. You help them through their various health crises. You watch them slowly slip away from you over the course of years. You know that, near the end, they are likely in pain all the time but will expend whatever energy they have to keep you from seeing it. You eventually face that day when you must make the decision: quality of life is more important than quantity; is it time to say goodbye? You know the drill.
While reading In the Dry Leaf at AmbivaBlog, I immediately recognized the sentiment Amba so touchingly relayed.
I then followed the link to read My old dog at Creek Running North. Amba got it right: "Thanks to Chris for saying the almost unsayable." There's just too much there to quote, and all of it true and shared. Go now; read it.