On January 5, 1959, Clarke eloped to Las Vegas and married Ralph Falk II.[4] Their second child, Melanie Borden Falk, was born in April 1961.[5] The relationship later ended in divorce.[2] On September 28, 1985, she married William Joseph McDonough at their home in Chicago.[2] He served as president of the Federal Reserve Bank of New York for 10 years and died in 2018.[6]
Clarke was a prominent fixture of Chicagoan high society in the North Shore suburbs, known for her parties. She developed a similar reputation in Mexico where she founded the Cuernavaca Racquet Club.[7]