Man, I am so sorry to hear about that. I understand how you feel though, I had to go through a very similar situation with my dog not too long ago (at least it doesn't seem too long ago :( ). Mine got very sick and became too weak to recover and was in a lot of pain, so I had to make that dreaded decision. I know it was for the best, as I know you made the right decision. It's never easy, but just remember the good times, and that you did the right thing for you best friend. He'd be licking your face right now thanking you! Take care my friend, and don't let it eat you up too bad.