Feel for you a lot, lost our old/main dog 4-5 weeks ago. Nothing fills the void, and nothing can step into the shoes.
He had his leg pinned and plated, came back, got nearly finished off by a T##t of a rotweiller, he came back.
You try to not get that attached, knowing they are working dogs, but it's the work that get's you attached.
Any working dog has it's days numbered as soon as it's born, but they are good days, the best days.
Sorry for you.
John.