Complex sentence: Meanwhile, the millionaire father has an affair with a supposed Countess, who turns out to be a lion tamer, and his niece, Daisy, marries a young Marquis, but she refuses to be anything but his friend.
Split into simpler sentences: Meanwhile, the millionaire father has an affair with a supposed Countess, who turns out to be a lion tamer. Also, his niece, Daisy, marries a young Marquis, but she refuses to be anything but his friend.