Prom mom by Laura Lippman

Two decades ago, Amber Glass’s life changed forever. No-one had even known she was pregnant – including Joe, her date. Afterwards, she left town for good – and hasn’t seen Joe since. But she knows he hasn’t left, that he’s working for his father’s real estate company, married to a cosmetic surgeon. Child free. Now Amber is back, and as the two of them tentatively start to renew their once unlikely relationship, will their secrets and motivations finally destroy everyone around them?