Tec, how come God didn't save Noah's entire household? Why did he specifically select only his wife, sons and daughters? Surely, Noah had grandparents, uncles, aunts, nieces, nephews and servants? Why not throw them in the Ark? It was because they were captive to the seed of the serpent which is discussed in detail in Genesis 3 and 4. Peter says that spirits were bound in chains after the Great Flood. God sent those who fell from heaven into the abyss, or the land of the dead, packed 'em right in there. Genesis 6:11 speaks of a totally violent world which would mean Noah's family was a party to that violence. Why would he want to bring them with him? So they could bring their insanity into the new world?
Now, fast forward to the story of Christ. What was his criteria for selecting his apostles? Ever wonder why the word "apostle" is so similar to the world "apostate"? Christ was selecting people who were totally opposed to the system they were captives to. He knew that by choosing them they were going to have a hard life that would likely end in torture. Naturally, he would choose people who didn't have strong ties with their family. If God truely IS Love, then Christ would have taken into account many factors in determining who held the roles. Because of the cost.
It's similar to the American Revolutionary War. Their was a solid wall between the one's loyal to the monarchy, who were called "Loyalists", and those opposed. If Christ came in that time do you think he would have chosen a bunch of loyalists as his messengers? No, he would have chosen people who strongly opposed because they would have the most incentive to help. Their very nature would separate themselves from their families who chose to exchange freedom for security.
Truth IS the sword that drives family's apart and always has been. In a world of tryanny, truth means resistance and resistance is taking a side. The problem is when cults, lead by people, wrongly assume the role of Christ, or Truth, which means they are taking the role of the sword, which is too heavy for them to lift.