That really sucks, my thoughts go out to you. Watching animals go is really difficult. I lost my 8 year old beagle to cancer 2 years ago and it was the hardest thing to see a little innocent creature being destroyed by an awful disease. I was extracting pee out of him every few hours to keep him alive in his final days but as Ginxy said, there comes a time when we have to let go, as hard as it is. He passed with in my arms with his face in a bowl of ice cream, I will never forget that. And of course I start tearing up just thinking about it.