Common decency by Susannah Dickey

Since her mother’s death, Lily has withdrawn from the world, trapped between grief and anger. She has to break out of this damaging cycle – but how? Upstairs, Siobh?n is consumed by her affair with a married man. Her days revolve around his sporadic texts and rare visits. She barely notices the strange girl who lives below and dawdles in the foyer. But Lily is keeping a close eye on her neighbour, whose life seems so much better and more fulfilling than her own. When resentment evolves into something darker and more urgent, she decides to teach Siobh?n a lesson.