NEW YORK -- Getting involved with purported self-help sage Keith Raniere meant having no say on whether to get an abortion, being tasked with monitoring a billionaire's hacked email account and getting banished alone in a bedroom for nearly two years after showing interest in another man.

That was the price a government witness against Raniere says she paid for following edicts that sought to make his abusive and illegal behaviour seem normal.

"I became broken pretty quickly," she said about her captivity. "There were times when I think I went crazy."

The disturbing testimony came during the fourth week of a New York City sex-trafficking trial that's exposed the dark underbelly of a once-thriving organization based in upstate New York called NXIVM. The woman, whose name hasn't been disclosed to protect her privacy, gave her third day on the witness stand on Wednesday.

Prosecutors say the 58-year-old Raniere was a con man who peddled expensive self-fulfilment courses as a cover for mentally and sexually abusing female followers through shame and humiliation, including some in a secret society of brainwashed "sex slaves" he had branded with his initials. The defendant's lawyers insist that he had no criminal intent and that his interactions with the women were consensual.

The 33-year-old witness, who's facing cross-examination on Thursday, was among three sisters from Mexico whose family sent to live in the Albany-area NXIVM community to learn from Raniere in the mid-2000s. She testified that over time, he stole the innocence of each of them by manipulating them into having sex with him when they were less than half his age, the youngest starting at 15.

Raniere was insistent that his sex partners not use birth control, the witness said. That resulted in pregnancies for all three sisters ending with abortions that were treated as routine, she said.

He reacted to her distress over the end of her own pregnancy by nonchalantly telling her it "was an opportunity to lose weight and get fit," she said.

The alleged victim also detailed how she was part of an effort to spy on billionaire Edgar Bronfman Sr. after the late former Seagram chairman was quoted in 2003 as saying he thought NXIVM was a "cult." She said the group hacked into Bronfman's email account after his daughter, NXIVM devotee Clare Bronfman, installed spyware on his computer.

The father was seen as someone who "had shifted to the enemy side" and "was out to destroy Keith," she said.

Clare Bronfman avoided going to trial with Raniere by pleading guilty in April to fraud and other charges.

There was another instance when the witness confided to Raniere that she was attracted to another NXIVM member, thinking Raniere would mentor her on the budding romance, she said. But after she told him about their first kiss, he flew into an irrational rage and accused her of trying to "destroy" him.

The witness testified that after that, Raniere would only communicate with her through email. His emails scolded her for her "pride" and ordered her to fast while trying to make amends for what he labeled an "ethical breach."

By 2010, a member of Raniere's inner circle ordered her into a bedroom with the consent of her family -- also NXIVM true-believers -- and ordered her to beg for his forgiveness under threat of being returned to Mexico. Her return there ultimately happened, but not before she suffered "completely alone for a day, then a week, then a month, then years" with not clear directions on how to win permission to leave, she said.

She contemplated suicide by swallowing cleaning fluids before concluding that she had nothing to lose by finally leaving the room without approval from the man known as "Vanguard" within NXIVM, she said. She marched out and found him at a social gathering, getting satisfaction seeing him duck into the crowd at the sight of her, she said.

She recalled being grabbed and put into a car before she could confront Raniere further. It was the last time she would see him before the trial.