Love and Friendship — Alison Lurie

Faculty wife Emily Stockwell Turner is beautiful, rich, and principled. However, five years in a marriage devoid of passion is enough to propel Emmy, despite her principles, into an affair with silver-tongued Will Thomas, a self-confessed libertine. The shocking, unforeseen consequences of their affair shatter Emmy's most cherished delusions about friendship, romance, and the ties that bind.