Not a matter of guilt or blame. It's one of those life lessons that ends up being either learned well, or not at all. I've seen far too many dogs tossed out for this reason or that when they should not have been. This is not to say that I do not sympathize with the situation and feel sorry for the loss, but I want to be sure that both sides of the fence are clearly visible through the grass. If not for this time, then for down the road with another dog, cat or critter of some kind.
Ah well.. I've said my two cents worth. Sorry for your losses.