The narrator tells us that, for anything to be accomplished in a household, husband and wife must either be in total disagreement or perfect harmony.
Anna and Vronsky are in an indeterminate stage, so nothing is accomplished, although they both want to leave Moscow and take up residence in the country.
Anna believes that Vronsky's love has diminished, while Vronsky believes that she's doing nothing to ease the poor social and professional situation that he has put himself into for her sake.
Anna is insanely jealous, reasoning that if his love for her has lessened, part of it must be lavished on some other woman or women.
Her biggest fear is that he might marry someone else. This fear was prompted when Vronsky told her that his mother was trying to set him up with some young princess.
Anna constantly loses her temper with Vronsky, blaming him for everything about her situation. To her, even his tenderness takes on a bored, complacent tone.
Earlier in the day, Anna and Vronsky had fought over Anna's education of Hannah, the little English girl that she has taken under her wing. Finally Vronsky calls her interest in Hannah "unnatural."
This sends Anna into a tailspin, because she sees it as a direct attack on the world she has built for herself while in Moscow.
Vronsky spends the following day away from home. Anna reasons with herself as she waits for him, concluding that they need to go to the country. She reassures herself that he loves her and that she loves him, and that the divorce will come any day now. She orders her trunks packed.