The young Irish writer Sally Rooney follows up her celebrated debut novel, "Conversations with Friends," with a story of Connell and Marianne, two millennials who meet in high school, go to college together in Dublin, and have a tumultuous on and off relationship. It's a deceptively simple story and perhaps self-consciously echoes the marriage plot of so many 19th century novels. I think criticisms of the protagonists "likability" or "narcissism" are entirely beside the point. They are complex, difficult people who struggle against the expectations of "normal people." As with "Conversations," Rooney's psychological understanding and insights are impressive. With only two novel, Rooney has become one of my favorite novelists, and I'll read anything she writes.