Heathcliff . . . shall never know how I love him . . . he’s more myself than I am. Whatever our souls are made of, his and mine are the same. . . .
Nelly is in the midst of hiding Hareton from Hindley when Hindley bolts in and seizes the boy. Stumbling drunkenly, he accidentally drops Hareton over the banister. Heathcliff is there to catch him at the bottom of the stairs.
Later that evening, Catherine seeks out Nelly in the kitchen and confides to her that Edgar has asked her to marry him, and that she has accepted. Unnoticed by the two women, Heathcliff listens to their conversation. Heathcliff hears Catherine tell Nelly that she cannot marry him because Hindley has cast him down so low; to marry him now would be to degrade herself. Heathcliff withdraws in a rage of shame, humiliation, and despair, and thus is not present to hear Catherine say that she loves him more deeply than anything else in the world. She says that she and Heathcliff are such kindred spirits that they are essentially the same person. Nonetheless, she insists, she must marry Edgar Linton instead.
That night, Heathcliff runs away from Wuthering Heights. Catherine spends the night outdoors in the rain, sobbing and searching for Heathcliff. She catches a fever, and soon she nears death. The Lintons take her to Thrushcross Grange to recuperate, and Catherine recovers. However, both Mr. and Mrs. Linton become infected and soon die. Three years later, Catherine and Edgar marry. Nelly transfers to Thrushcross Grange to serve Catherine, leaving Hareton in the care of his drunken father and Joseph, the only servant now remaining at Wuthering Heights.
Noticing the clock, Nelly again interrupts her narrative, saying that it is half past one, and that she must get some sleep. Lockwood notes in his diary—the same book in which he has set down Nelly’s story—that he, too, will go to bed now.
In this section, Nelly brings to conclusion the story of Heathcliff and Catherine’s childhood, with Heathcliff leaving Wuthering Heights the night Catherine decides to marry Edgar Linton. In the climactic scene in which Catherine discusses with Nelly her decision to marry Edgar, Catherine describes the conflict between her love for Heathcliff and her love for Edgar. She says that she loves Edgar because he is handsome, rich, and graceful, and because he would make her the greatest lady in the region. However, she also states that she loves Heathcliff as though they shared the same soul, and that she knows in her heart that she has no business marrying Edgar. Nevertheless, her desire for a genteel and socially prominent lifestyle guides her decision-making: she would marry Heathcliff, if Hindley had not cast him down so low.
Heathcliff’s emotional turmoil is due in part to his ambiguous class status. He begins life as a lower-class orphan, but is raised to the status of a gentleman’s son when Mr. Earnshaw adopts him. He suffers another reversal in status when Hindley forces him to work as a servant in the very same household where he once enjoyed a life of luxury. The other characters, including the Lintons and, to an extent, Catherine—all upper-class themselves—prove complicit in this obliteration of Heathcliff’s hopes. Inevitably, the unbridgeable gap in Catherine’s and Heathcliff’s social positions renders their fervent romance unrealizable on any practical level.