Complex sentence: However the most important form of conflict and tension is that within Kingsley himself, because of his actions, Kingsley has lost his wife and son; an unimaginable sacrifice which Kingsley has to deal with.
Split into simpler sentences: However the most important form of conflict and tension is that within Kingsley himself. Because of his actions, Kingsley has lost his wife and son, an unimaginable sacrifice which Kingsley has to deal with.