One Italian Summer by Rebecca Serle

 Katy and her mother, Carol, are best friends who do everything together. Katy asks her mother for advice on everything (sometimes to her husband's dismay). So when her mother dies, Katy is adrift. The two of them had been planning a trip to Italy so Carol could show Katy where she spent some of the happiest days of her youth. Katy decides to go by herself to Positano (which, after reading this book, I am dying to visit too). One day when she's out walking, Katy meets the younger version of her mother. This Carol has no idea that Katy is her daughter, she is just drawn to the young American women. The two of them strike up a friendship and start hanging out together, which is an eye-opening experience for Katy.  At the same time, Katy is trying to decide whether or not to stay married to her husband, Eric. She starts up a flirtation with a handsome American named Adam who is staying at the same hotel. And what could go wrong there?

It's a fascinating journey as Katy learns more about herself, her mother, and her marriage--and the explanation of how Katy could meet the younger Carol was not what I expected.