Abelar met Castaneda when she was 19 years old and a student at University of California, Los Angeles where she eventually earned her Master’s degree and Ph.D. in Anthropology. In 1973, Castaneda purchased a compound on Pandora Avenue in Westwood, Los Angeles, and soon after Abelar (she was still known as Maryann Simko at this time), along with Regine Thal and Kathleen Pohlman, who would come to be known collectively as "the witches", moved in. In 1974, Samurai magazine published photos of Regine Thal doing karate exercises. In the article, Abelar is called "Anna Marie Carter".
In keeping with Castaneda’s philosophy of "erasing personal history", the witches maintained a tight veil of secrecy. They used numerous aliases and generally did not allow themselves to be photographed. Not long after moving into Castaneda’s compound Maryann Simko changed her name to Taisha Abelar. Likewise, Regine Thal changed her name to Florinda Donner and Kathleen Pohlman hers to Carol Tiggs.
Abelar claimed to have been one of Don Juan’s four students and says she spent a year in his “magical house” in Mexico. In 1992, her book The Sorcerer’s Crossing: A Woman’s Journey, which documents the training she received from the female members of don Juan’s group, was published by Viking Books.