Bronte portrays difficulties in the lives of women by showing how much power a husband had over a wife. This can be illustrated by examining the marriage of Isabella Linton and Mr. Heathcliff.
Isabella falls in love with Heathcliff, seeing him as "a hero of romance," in Heathcliffe's sneering words. He marries her even though he despises her: he wants to hurt her brother Edgar, and he wants to control any claims to inherit Thrushcross Grange she or her children might have.
As soon as he marries her, Heathcliff begins to treat Isabella cruelly. He admits he has run "experiments on what she could endure, and still creep shamefully cringing back," but is careful to tell Nelly Dean, to whom he is speaking, "I keep strictly within the limits of the law." Although he might be within legal bounds, Isabella says, "He's ... a monster and not a human being! ... The single pleasure I can imagine is to die or see him dead."
Heathcliff tells Nelly to remember Isabella's words about wanting him dead "if you are called upon in a court of law." His cruelty has incited Isabella to lash out at him by wishing him dead, and now he uses this against her: "you're not fit to be your own guardian, Isabella," he says. Because Edgar has disowned her, Isabella, as a wife, is at the mercy of a husband who cries: "I have no pity! The more the worms writhe, the more I yearn to crush out their entrails!"
Later, Heathcliff orchestrates the marriage of his son by Isabella to Edgar's daughter. The son is well schooled by his father in how much raw power a husband has: "papa says everything she has is mine ...her nice books are mine ... all, all mine." Isabella's son, named Linton, also tells Nellie that "Papa ... says I am not be soft with Catherine: she's my wife ..."
These examples demonstrate the extent of patriarchal power and how women could suffer under it. Bronte does not soften the picture, so it's little wonder the book was unpopular in her time.