While it's true that this book is sad, it's an essential read to understand what life might be like for those living in less privileged conditions. I wouldn't recommend it if you're looking for something light and uplifting, but if you're looking to expand your horizons and step out of your comfort zone, I'd highly recommend this book. It's about loss and hopelessness, but it's also about family, love and the power we have to overcome great suffering.
That being said, I didn't find the ending of the book that sad. Without spoiling the plot, I felt it ended on a hopeful note.