In later years, Sybil Christopher lived a relatively quiet life running a little village theatre at the far end of Long Island in New York State. But 50 years ago she was a key player in one of the most dramatic and certainly the most publicised show-business romances of the 20th Century.
She was the wife cast aside when Richard Burton and Elizabeth Taylor met on the set of Cleopatra (1963) and the passion between the film's two main protagonists spilled over into real life.
Sybil met Burton on the set of his first film, the Welsh period drama The Last Days of Dolwyn in 1948. Burton had done some stage work, but was still a virtual unknown at the time. He had a major supporting role in The Last Days of Dolwyn. Sybil was an extra. Like Burton, she came from the south Wales coalfields and they immediately hit it off.
She was only 19 when they wed on February 5, 1949, beginning married life in a rented room in Fulham, London.
She appeared in the 1949 West End production of Harvey, played Lady Mortimer in Henry IV at Stratford-upon-Avon in 1951, and voiced Myfanwy Price in the 1954 BBC radio version of Under Milk Wood, which also featured Burton. But she effectively gave up her dream of an acting career when Burton's took off.
They had two children in the late 1950s and Sybil seemingly tolerated her husband's numerous affairs, which included relationships with Claire Bloom and Jean Simmons, but the relationship with Elizabeth Taylor was quite different.
It tore two marriages apart – that of the Burtons, and also that of Taylor and her husband, the singer Eddie Fisher, whom Taylor had lured away from his then wife and Taylor's supposed best friend, the popular American actress Debbie Reynolds.
Bitter divorce proceedings followed. Sybil Burton sued her husband for divorce on the grounds of abandonment and cruel and inhuman treatment. She won custody of their two daughters and a settlement of $1m.
She also received a great deal of public sympathy. The public were fascinated by the ongoing Burton-Taylor story, but the public relationship with the starry couple was always somewhat ambiguous.
She was born as Sybil Williams into a Welsh-speaking household in the village of Tylorstown in the Rhondda Valley in 1929. Her father was an under-manager at a local colliery. Her mother died when she was 10 and her father when she was 15 and she went to live with an elder sister in Northampton, where she worked as a window dresser.
She had already begun acting in amateur drama in Wales, studied at the London Academy of Music and Dramatic Art and she was still a student when she met Burton during the making of The Last Days of Dolwyn.
"I loved theatre and what I was doing, but I certainly wanted to go as a wife to America when Richard was offered a job there," she said in an interview with The New York Times in 1994. "It was clear to me that I wasn't making a sacrifice. I knew Richard would have an exciting career and that it would be fun, two Welsh kids on the Queen Mary, travelling first class.
"In retrospect, that is what I would like to preserve, that nice warm feeling I had on the boat. I had the 23-year-old, the best. I look at the films, but I don't know that other guy. I had the golden boy."
The Burtons subsequently moved to Switzerland to escape Britain's high taxes and had two daughters – Kate, who is also an actress, and Jessica.
The affair between Burton and Taylor did not end with the filming of Cleopatra. Taylor actually followed Burton to Switzerland and took over a chalet and the relationship continued in London when they began shooting the film The VIPs (1963).
They had adjoining suites at the Dorchester, while Sybil and the children were staying at a property Burton owned in Hampstead. Sybil Burton finally decided enough was enough and left for New York with the children, and she would subsequently make her home in the US.
She became involved in theatre in New York and was one of the founders of the New Theatre on 54th Street.
Sybil Burton also married again, to the actor Jordan Christopher who was 10 years younger than her. She had a third child with him. He died in 1996.
In 1991 she became one of the founders of the Bay Street Theatre, a non-profit theatre in the Sag Harbour community at the east end of Long Island, in New York State. She served as its artistic director until last year.