I can confidently say that the author of 'The Heartbreak Book' isn't a single individual but rather a collective of experiences that many writers have captured beautifully. However, if we're talking about iconic heartbreak novels, 'The Fault in Our Stars' by John Green is a masterpiece that delves into love and loss with raw honesty. Another poignant read is 'Norwegian Wood' by Haruki Murakami, which paints heartbreak in such a visceral way that it stays with you long after the last page.
For those who prefer contemporary takes, 'It Ends with Us' by Colleen Hoover is a modern exploration of love's complexities and the pain of letting go. Sylvia Plath’s 'The Bell Jar' also offers a unique perspective on emotional turmoil, though it’s more about personal struggle than romantic heartbreak. Each of these authors brings something unique to the table, making their works unforgettable for anyone who’s ever experienced the sting of a broken heart.