Her ardent liberal Democratic views clashed with those of her Republican husband and apparently created tensions in the marriage.
After America entered the Second World War in December 1941, Marietta accepted a post as part of the American delegation assisting the British Ministry of Information.
[2] When her husband returned at the end of the war Huston departed for California at her request to wait for her to obtain a divorce.
[5] At that point, however, Marietta and her husband traveled to Barbados to stay with Nancy and Ronald Tree, a grandson of retail magnate Marshall Field and MP for Harborough, Leicestershire.
Marietta moved into Tree's home, Ditchley Park, but found herself bored with English country life.
[2][9] Marietta Tree immediately joined the Lexington Democratic Club, and two years later was elected the county chairwoman.
Tree’s husband was unfazed by the affair, perhaps due to his bisexuality,[5] and even invited Stevenson to the couple's homes in New York, Barbados and London.
On July 14, 1965, Tree and Stevenson were walking in London when he suffered a heart attack, and later died at St George's Hospital.
[4] Tree supported herself in later years by getting herself appointed to several well-paid directorships, including the boards of CBS, Pan Am, and Lend Lease Corporation of Australia.
[4] Isaiah Berlin characterized her political leanings as "a progressive, liberal figure who was mixed up with a lot of naive left-wing sympathizers.