qnli question: What term describes the qualities of the relationship between Frédéric and Liszt? sentence: Some commentators point to events in the two men's romantic lives which led to a rift between them; there are claims that Liszt had displayed jealousy of his mistress Marie d'Agoult's obsession with Chopin, while others believe that Chopin had become concerned about Liszt's growing relationship with George Sand.