Why Christian Need Other People?

God doesn't want us to be lonily and isolated,because without other people interating with you ,your community will stop functioning. Let say you go on vacation and you visit a resurant and there is no cook, tack a air plane to your next location and you have to fly it,or be the police,security guard,doctor ,bus driver .We need other people if they are not christian or not to make the world go around.This is still God's world and if he wants to destroy it he would have did so ,before the flood or after.