Story of the Faithless Wife who Burnt herself with her Husband's Body, from Somadeva's Katha Sarit Sagara (The Ocean of Streams of Story)
There was a merchant in this very city named Balavarman, and he had a wife named Chandrashri, and she beheld from a window a merchant's handsome son, of the name of Silahara, and she sent her female friend to invite him to her house, and there she used to have assignations with him in secret. And while she was in the habit of meeting him there every day, her attachment to him was discovered by all her friends and relations. But her husband Balavarman was the only one who did not discover that she was unchaste. Very often men blinded by affection do not discover the wickedness of their wives.
Then a burning fever seized Balavarman, and the merchant consequently was soon reduced to a very low state. But though he was in this state, his wife went every day to her friend's house to meet her paramour. And the next day, while she was there, her husband died. And on hearing of it she returned, quickly taking leave of her lover. And out of grief for her husband she ascended the pyre with his body, being firmly resolved, though her attendants, who knew her character, tried to dissuade her.
From: Somadeva Bhatta, The Ocean of Story. Vol. V. Translated by C. H. Tawney. Edited by N. M. Penzer. London: Privately printed, 1926, 19.