Frost at Midnight — Elizabeth Falconer

Misha had grown used to Giles, her English lover who spent part of his time at her elegant Paris apartment. She didn't expect him to marry her, but she did expect fidelity - until she discovered that he had a partner and child back home in London. Paul, Misha's senior colleague at the hospital where they both worked, was himself trapped in a loveless marriage. Mutual unhappiness brought Misha and Paul together, and at Paul's crumbling ancestral manor house at Froissy they found unexpected joy and fulfilment. But jealousy and threats of exposure tore them apart, and Misha fled from Paris, taking her medical skills to work in famine-struck Africa. Her health and happiness seemed to have vanished forever, but an unexpected meeting brought her back to Paris and to her true destiny.