The lucky humans were just sent to work for the pack until they died from either sickness or old age. The humans that were mated to wolves typically lived a much crueler fate of imprisonment with that wolf. Most of those humans are never seen again, not even by their loved ones. Most of the stories of how the wolves treat their human mates are created by frantic mothers and angry fathers, but if how they treat the rest of the humans is any indication, then the life of a wolf's mate must be horrific.