The book is a real page-turner, making you really want to know how it ends. Death? Marriage? Both. With Catherine dying halfway through the novel, finding out what happens to Heathcliff becomes all the more important. The last page of the book has Lockwood leaving Wuthering Heights for Thrushcross Grange, stopping to take one last look at the soon-to-be-married Hareton Earnshaw and Catherine Heathcliff.
Wuthering Heights really shows the difference between "ending" and "closure." Sure the book ends, as does Nelly's narration, and certain threads of the story are neatly tied together: domestic harmony returns to the home, Hareton is able to read his name above the threshold, and his ownership of the house suggests that all is right with property and inheritance. When Nelly picks up the narration one last time, she seeks to provide closure to Heathcliff's story and to the reunification of this generation of Earnshaws. Like a Shakespearean comedy, the story ends with a marriage, as Nelly explains in almost maternal tones: "The crown of all my wishes will be the union of these two; I shall envy no one on their wedding day. There won't be a happier woman than myself in England!" (32.111).
The novel begins with Lockwood struggling to enter Wuthering Heights (with all its vicious dogs, locked gates, and the forbidding landlord) and ends with open windows, sunshine, and lovers. But for all the romantic conclusions and gratification we get from Hareton and Catherine, the lovers we are really thinking about are six feet under ground.
Lockwood can't resist passing by the graves of Catherine, Edgar, and Heathcliff, whose plot is not yet covered in moss, grass, and turf because he was just buried. Looking over the peaceful scene, with moths fluttering about, Lockwood can't imagine that they won't all three rest in peace. What?! Has he not just heard the whole story? We can be pretty sure that anything involving Catherine and Heathcliff will not be peaceful. It's almost as if Brontë teases us with this serene image of the moors after detailing several hundred pages of conflict. So, while Lockwood interprets closure in his narrative, we as readers have become more savvy than him knowing that there are many ways to read the novel's ending.