One Day, by David Nicholls.
Despite trudging through this book and deliberately treating it like a burden at times, I loved it so much. The trudging came into play when the writing felt self-indulgent and circular but the more I read, the more necessary all the detail revealed itself to be. It was such a love story; I wanted to shake the characters at times. I was so involved in their lives, it felt weird coming out of the story, but I was really glad I was in it when I was there. And as always, the book > the series on Netflix.