Wife by Charlotte Mendelson

When Zoe Stamper meets fellow academic Dr Penny Cartwright at a party, she seems impossibly glamorous to Zoe, who is, after all, several rungs down the academic pecking order – and a nervous ingénue as far as Penny’s sophisticated circle is concerned. But Penny leaves Zoe a cryptic note, and a passionate affair ensues . . .

Once Penny confesses all to her live-in lover, Justine, their path is cleared to a life of mutual contentment and marital bliss. But there is something else Penny needs as badly in her life as Zoe’s adoration, and thus the beginning of their affair might also have signalled its end.