It's tough to really call Wuthering Heights a romance, since the two lovers spend so much time making each other miserable. Still, we know Catherine and Heathcliff experience some sort of transcendent romantic and sexy connection... even though Catherine is so derisive of Heathcliff's social standing that early on in the story she questions his capacity to love at all.
Heathcliff and Catherine's fanatical, impassioned affection connects to the nostalgia of their childhood and reaches beyond the grave into the afterlife, so there's definitely a love connection going on. All of the other examples of love—or, more precisely, marriage—are diminished in comparison, except perhaps that of Cathy Heathcliff and Hareton Earnshaw.
Questions About Love
Catherine confesses to Nelly that she loves Edgar but that she is also marrying him to elevate herself socially. Does she really love Edgar? Is Edgar a lovable character?
Why does Isabella marry Heathcliff?
How does the relationship of Cathy and Hareton Earnshaw compare to that of Catherine Earnshaw Linton and Heathcliff?
Chew on This
In the various relationships, Brontë explores the dimensions of romantic, platonic, and erotic love, but mystical love seems to transcend all of them.