Actually, I read LOTR it when I was in 5th grade and loved it. Harry Potter I would have thought as meaningless garbage. The characters are much stronger in LOTR than in Potter.
not one character has a father, mother, brother, sister, wife or husband
Actually in Book one: Sam has a father, Tom Bombadil has a wife, Arwen has a father...should I go on? Guess your reading skills need improvement.
And their relationships figure into the story exactly how?
There is a reason why middle aged British men wrote stories about men who never really touch or interact with women, but I won't tax your mind by asking you to imagine why.