Joan Castleman is a fictional character from the novel "The Wife" by Meg Wolitzer. She is portrayed as the long-suffering spouse of a successful author, grappling with her own sacrifices and ambitions throughout their marriage. The story explores themes of gender roles, identity, and the complexities of relationships. In the narrative, Joan's character becomes increasingly significant as she confronts the realities of her life and the choices she has made. The novel delves into her internal struggles and the impact of her husband's fame on her own sense of self, ultimately leading to a powerful revelation about her true identity.