In Chapter 10, Catherine is beside herself with delight when Heathcliff returns after three years absence. No one has seen or heard from him in all that time. Although newlyweds, Ellen explains that Catherine and Edgar are already solidly settled at Thrushcross Grange as man and wife, Catherine assuming her new role as mistress of the house and fitting in quite nicely except for spells of quiet sadness, which Edgar attributes to her illness that occurred after Heathcliff's disappearance and took the life of both of the elder Lintons.
Ellen's description of Heathcliff's physical improvements from rough dirty farm boy to handsome, fiery-eyed, athletic gentleman are a vivid constrast to Edgar's small, pale politeness. Catherine absolutely gushes at Heathcliff's unexpected presence much to her husband, Edgar's dismay. When Catherine leaves Edgar's side and her wifely duties at the tea table to clasp Heathcliff's hands while he callously exposes his negative feelings about their marriage, his plan to get even with her brother for his abuse and his admission that his years away to make his fortune were all for her, Edgar still struggles to act the polite gentleman even though he's been seriously insulted in his own parlor.
Catherine, on the other hand, sits at the table with Heathcliff, completely ignoring her husband as though he doesn't exist and is so excited she can't eat or drink or keep her eyes off Heathcliff. Later, she can't sleep because of her ongoing rapture over Heathcliff's return and wakes Ellen to tell her how upset Edgar was at her wanting to discuss Heathcliff's vast improvements. She can't understand why her husband isn't happy for her happiness.
I imagine this was a pretty sexual and shocking scene when it was first published. Women weren't believed to be able to feel sexual excitement or passionate urges, but live their dutiful and oppressed lives with the main emphasis being making their husbands happy and comfortable. Catherine emotionally and physically ignores her husband as she glows with excitement over Heathcliff's presence. She even fears his visit is a dream that she'll be doomed to wake up from and soaks him in with all of her senses. She is high on Heathcliff.
This scene is one of my favorites from the book exposing the dull depressing, although leisurely, existence of the well to-do ladies of country society in England in the early 19th century. It hints at the lack of emotional, physical and sexual freedom they had in spite of their wealth and ease.