It's interesting to see how the book divides readers into different camps of opinion. I understand why you are in a group that maintains a love-hate relationship with him.
Your point about obsession and how it dominates and clouds the characters' minds is spot on. "Wuthering Heights" is not a conventional love story; it explores obsession, the desire for revenge, and the consequences of unbridled passions.
Brontë does not skimp on showing how trauma and environmental influences can warp love into something destructive.
As for the characters, it is characteristic of the writer to break traditional molds by presenting morally ambiguous characters and anti-heroes, which was quite radical for her time.
In my opinion, what makes this novel a timeless masterpiece is its ability to evoke intense emotions in readers and explore the depths of the human psyche.
Human mind is a fascinating thing and is a never ending source of exploration. Obsessions are the worst, how they gradually build up, and from something that was innocent to begin with, it morphs into a state where it's ludicrous and out of control. Love is a powerful trigger for it. While I hated seeing the characters being naive, defenseless and tormented, I love that the young Brontë woman had courage to write such a striking novel.
Part of what makes her transcend in literature is her courage, especially being a woman and in her time.
On the other hand, good literature consists of digging into the wound and treading on the delicate terrain of the human mind. To go beyond society's limits and beyond where it hurts and provokes.