Very sad news, i'm sorry for your loss BUT, these are the things that can happen when out, hunting can be very dangerous for our dogs. I've lost 2 over two years with another smashed so bad he's now in semi-retirement, so I know how much it hurts.
No dog is irreplaceable, if you love the game your in, you'll take stock, think about where it went wrong, think about and obtain your next dog, bring it on better (as we all can) and get yourself back in the game. Life's too fecking short!
Thanks for the support folks