Mary Garth, Featherstone's niece by his first marriage, is charged with the care of the sick old man. Fred is also madly in love with her. He asks Rosamond if Mary mentioned anything about him. He fears that Mary has heard the rumor about his gambling debts. Rosamond replies that Mary only said that he is unsteady and that she would refuse to marry Fred if he proposed.
Casaubon himself suffers from unrealistic notions regarding the ideal wife. Dorothea may not relate to him as an individual, but he does not relate to Dorothea as an individual either. He wants a completely submissive helpmate. He doesn't court Dorothea for what she is, but for what he thinks he can make her be.
Dorothea is a good deal less submissive than he believes her to be. Despite numerous clues, he fails to recognize her stubborn, independent streak. Dorothea scorns the social constraints on women. She doesn't want to limit herself to the "proper" education for women. Dorothea wants to pursue those studies considered "too taxing." Dorothea fails to realize that Casaubon doesn't want an equal partner. She even deludes herself into thinking she wants to submit to him. His ideal wife is not far from conventional ideals of womanhood. Wives are generally expected to live through their husbands, not independently of them. Dorothea's idealized notion of self-sacrificing virtue ignores the need to balance self-interest and the interests of others.
Dorothea subscribes to her own ideal notion of herself. She denies her own personal desires. She wants to learn Latin and Greek for her own sake, not merely to help Casaubon. She doesn't merely want a wise husband; she wants to be wise herself. The social constraints placed on women force her to take a circuitous route to wisdom. Although it is distinctly unfeminine to learn Greek and Latin, she can do so by submitting to another social convention; her unfeminine education is justified by notions of wifely duties. Her self-delusion arises partly out of a need to legitimize her pursuit of higher learning, but it also arises from her idealization of self-sacrifice.
People continually describe Dorothea and Casaubon with opposing metaphors. Casaubon is dry, old, and deathly; Dorothea is young and lively. Rather than complementing one another, they seem essentially opposed to one another. Dorothea's idealism also leads her to misinterpret the assistance Casaubon gives Will. He helps Will out of a strict notion of duty. Dorothea believes he does so out of a naturally generous nature.
Dorothea also wants passionate, tender affection from Casaubon. However, he considers her happiness in the same way he views Will's. He wants to do his duty as a husband. He studiously considers her comfort during the journey to Rome in the same dry, strict manner. He views his role as a husband in the same abstract terms of responsibilities. Dorothea continually feels rejected when she doesn't receive the emotional response she desires, and Casaubon continually feels inadequate as a husband when his responses upset her.