Julian Barnes's The Sense of An Ending is a novel about a middle-aged man coming to terms with how a cruel letter he wrote as a young man precipitated the suicide of a close friend. The book won the 2011 Man Booker Prize.
Retired arts administrator Tony Webster looks back to the 1960s, when he was an apathetic but intelligent teenager. He befriends Adrian Finn, impressed by the new student's philosophically complex answers to teachers' questions. Tony doesn't date seriously until he meets Veronica Ford while they are both attending university. Months after breaking up with Veronica, Tony receives a letter from Adrian informing him that he is dating Veronica. Tony dwells on the betrayal and responds with a letter denouncing Veronica as a "cock-tease" and suggesting that Adrian should ask her mother about whether Veronica was abused by her brother or father. Several months later, Adrian kills himself. Tony doesn't think about his involvement in Adrian's and Veronica's lives until he learns, forty years later, that Veronica's mother left him Adrian's diary in her will. Tony reconnects with Veronica, but she is unwilling to hand over the diary, which she claims to have burned. Veronica drops clues, however, including a page from the diary in which Adrian makes a calculation involving Tony's name. The calculation seems to justify his suicide. Veronica also shows Tony a developmentally disabled man who Tony can see is Adrian's son. Tony apologizes to Veronica for not realizing they had a child together, but Veronica says he still doesn't understand. After speaking with Adrian Junior's care worker, Tony learns the man is Veronica's mother's son. Because he suggested in his letter that Adrian speak with Sarah Ford about her daughter's "damage," Tony's action precipitated an affair between Sarah and Adrian, Sarah's pregnancy, and Adrian's death.
Exploring themes of aging, time, and remorse, The Sense of an Ending examines the pitfalls of trusting one's own inherently biased and unreliable memory. A film adaptation, directed by Ritesh Batra and written by Nick Payne, was released in 2017.