Who is Annabel Thwaite from The Emperor's Children and what is their importance?

Murray's wife is a lawyer and a compassionate citizen of New York City. She befriends everyone who needs her, and in this novel, everyone seems to need her for support. Murray and Marina revolve around her, looking to her for strength. Indeed, she is the one who gets things done. In each scene of the novel where Annabel is included, she is busy doing something: cooking, driving, planning the wedding, preparing coffee. Murray thinks and writes about the world, and Annabel does something in it.