Thirst For Love by Yukio Mishima

Book summary from Goodreads:

In Thirst for Love*, Japan's greatest modern writer created a portrait of sexual torment and corrosive jealousy that is as delicately nuanced as* Madame Bovary and as remorseless as Justine*. Yukio Mishima's protagonist is Etsuko, whose philandering husband has died horribly from typhoid. The young widow moves into the household of her father-in-law, where she numbly submits to the old man's advances.*