A few weeks earlier [February 1998], Mason had finally divulged her extraordinary secret...: the 75-year-old former college art teacher was the world's most famous psychiatric patient -- the real-life model for "Sybil," journalist Flora Rheta Schreiber's 1973 best seller about a woman so abused as a child that she developed 16 personalities, including women with English accents and two boys. The book was made into a 1976 TV movie starring Sally Field and was largely responsible for popularizing multiple-personality disorder -- until then, a rare diagnosis.
...Before the publication of Sybil, there were only about 75 reported cases of MPD; in the 25 years since, there have been, by one expert's estimation, 40,000 diagnoses, almost all in North America. The book had the blessing of great timing: it hit the public consciousness in the ascending days of feminism, when people were also beginning to grow concerned about child abuse. A quarter century later, by the time Mason lay dying in her bungalow, many experts were disputing the validity of the multiple-personality diagnosis and blaming the book for spawning a bogus industry of therapists who specialize in hidden abuse. At the same time, psychiatric historians and researchers have now begun to try to sort out the facts of the case that started it all.
Mason was raised in the small, conservative town of Dodge Center, Minn., the only child of Mattie and Walter Mason, a hardware-store clerk and carpenter; both were strictly observant Seventh-day Adventists.
...Despite painful memories of the repressive church in Minnesota, she remained devoted to her Seventh-day Adventist faith. "She was happy," Guy says.
In the summer of 1997, the cancer came back. Once again Mason declined medical treatment, telling Guy she had had "enough trauma in her life." She began giving away her books and paintings to friends and shredding her personal papers. She left most of the rest of her estate to a Seventh-day Adventist TV minister.