A Severed Head by Iris Murdoch

In this novel, a London wine merchant is living a seemingly comfortable life with his wife when his world is turned upside down by a series of shocking revelations. His wife confesses to an affair with her psychoanalyst, who is also his best friend, and plans to leave him. As he grapples with this betrayal, he begins an affair with his sister-in-law, only to discover that she is also involved with his wife's lover. The protagonist is forced to confront his own selfishness and immaturity as he navigates this tangled web of relationships.

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