What event prompts the Comtesse de Tournay to dislike and insult Lady Blakeney?

The Comtesse de Tournay's dislike for Lady Blakeney is primarily prompted by her perception that Lady Blakeney's husband, Sir Percy Blakeney, is a coward. This disdain is fueled by the Comtesse's own tragic circumstances, as she is a refugee from the Reign of Terror in France and sees the Blakeneys as emblematic of the aristocracy's indifference to the plight of those suffering in her homeland. Therefore, her insults toward Lady Blakeney stem from a mix of personal grief and her belief that the Blakeneys represent everything that is wrong with the aristocratic class.