Honey, Baby, Sweetheart by Deb Caletti. It's a funny, sweet, realistic book about growing up and realizing that you don't have to rely on other people to grow as a person. It also has a romance between older adults, which you don't see very often, especially in YA novels.
My favorite quote from the book, said by an older woman who talks about why she never got married after her husband died: A lady I will be, but a man's accessory, his handbag, no thank you. I will not be someone's ornament. I will not just be someone's honey, baby, sweetheart.