As I said, not love itself, but human nature in relation to love, hate and vindictiveness. The difference between Wuthering Heights and say, the story of Abelard and Heloise, is that in the latter the focus is on their transcendental love, while in the former it is on their various human failings. I've already explained my reasoning, but that is essentially the difference, for me.
I'd say that you have a broader definition of "love", with regard to what it encompasses in this context, is all.
1578.