During the Reign of Terror Marie-Louise was imprisoned as a "suspect", under the name of O'Murphy, at Sainte-Pelagie and later at the English Benedictine convent in Paris. After her release she married thirdly on 19 June 1795 with Louis Philippe Dumont (17 November 1765 – 11 June 1853), a moderate MP for Calvados in the National Convention and twenty-eight years younger than her; however, this union quickly failed, and after almost three years, they divorced on 16 March 1798. She never married again.