Concerning Lily by Sally Brampton

When Elizabeth Delaware, bored of her comfortable life, invites young, friendless Lily Clifton to meet her husband and friends, she cannot imagine the terrible consequences the invitation will have. For Lily is not just a stranger to London, she is a stranger to conscience.Elizabeth does not see Lily for what she is, nor can she see that her marriage to solid, dependable Charles is slowly crumbling. Even Elizabeth’s good friends, Bella and Daisy, both intent on salvaging the wreckage of their own relationships, are powerless to resist as Lily moves through all their lives, wreaking quiet but careless havoc.