The Midnight Library by Matt Haig is a novel that follows the life of Nora Seed, who finds herself in a library between life and death, with the opportunity to try out alternate versions of her life and find the one where she truly belongs. Regret and Choice: One of the central themes of the novel is regret and the choices we make in life. Nora Seed, the protagonist, is burdened by a multitude of regrets, ranging from career choices to personal relationships. The novel examines how these regrets have shaped her life and led her to contemplate ending it.