The Golden Notebook by Doris Lessing

The novel centers around a woman named Anna Wulf, a writer who keeps four notebooks, each representing a different aspect of her life: her experiences in Africa, her current life in London, a novel she is writing, and her personal experiences. As Anna's mental state deteriorates, she attempts to unify her fragmented self in a fifth notebook, the golden notebook. The novel explores themes of mental breakdown, communism, the changing role of women, and the fear of nuclear war.

The 167th greatest book of all time