Maybe in Another Life by Taylor Jenkins Reid. "A big tragedy happens just as a woman is making a decision. Alternating chapters tell the story of both paths she could’ve taken." After living in six different cities and holding a number of meaningless jobs, twenty-nine year old Hannah Martin still doesn't know what she wants to do with her life. She decides to move back to her hometown of LA and live with her best friend Gabby. During a night out with Gabby, Hannah reunites with her old high-school boyfriend, Ethan. Just after midnight, Hannah is faced with a decision to leave the party with her friend Gabby, or to stay with Ethan and get a ride with him later. In two parallel storylines, we see how each scenario plays out into totally different stories, with large-scale consequences for Hannah's life.