(CNN) -- Sara Hammon saw some of her sisters pulled out of school to be married to men they didn't know. She dreaded a similar fate. And so, she ran away from home before she was old enough to drive legally.
Sara Hammon says the prospect of an arranged marriage was "like marching to the guillotine."
She left behind 19 mothers, 74 siblings, and a father she says could never remember her name, even though he repeatedly molested her.
And, she left behind a culture she says was oppressive for young women.
Hammon recently gave CNN a deeply disturbing account of her life inside the polygamous sect whose leader, Warren Jeffs, goes on trial this week in Utah.
Jeffs is accused of being an accomplice to rape. The charge stems from his alleged practice of arranging polygamous marriages between child brides and older male followers.
Hammon is not directly involved in the charges against Jeffs, which concern an arranged marriage between a girl, 14 and her 19-year-old cousin. She left the sect before she could be placed in an arranged marriage. But she is one of its most outspoken former members. Watch Hammon describe her escape from a closed world »
"Probably the worst part of the whole theology," she said, " is the treatment of women and teaching women that they are not equal to men."
"They have to have a husband in order to get to the highest degree of heaven, and not only a husband but they have to allow the husband to have two other wives," she added.
Hammon was born in Hilldale, Utah, and raised in Colorado City, Arizona, towns where followers of Jeffs -- the President and Prophet, Seer and Revelator of the Fundamentalist Church of Jesus Christ of Latter Day Saints (FLDS) -- freely practice polygamy. Hear the words of the prophet »
The FLDS broke more than a century ago from the mainline Church of Jesus Christ of Latter-day Saints, based in Salt Lake City, Utah, over the practice of polygamy.
The Mormon church, which gave up plural marriage more than a century ago, has renounced Jeffs' group.
Hammon was the first 14-year-old girl to successfully leave the FLDS, she said. Almost 20 years later, she recalls the time she spent inside the compound as being filled with fear. She speaks out as part of her work with The Hope Organization, a non-profit group based in St. George, Utah, that assists victims of abusive polygamous relationships.
"There was a tremendous amount of abuse in our home," Hammon said. "It happened on a daily basis and there was all kinds: sexual, physical, emotional, mental. My brothers were sexually abusive. Some of my mothers were physically abusive."
But it was her father -- an FLDS church leader -- who terrified her. He began sexually abusing her before she turned 5, Hammon said. He even tried to molest her on his deathbed when she was 13, she said.
"For me, he was a very mean person. I didn't know him while we lived in the same house for 13 years and he had to ask me my name every time he saw me.
"In fact, the question he would ask is, 'What is your name and who is your mother?' and that was the only way he could identify that I was his child," Hammon said.
Three of her older sisters were placed in marriages before they finished high school, including one who was 16 when she married a 62-year-old man, Hammon said. She recalled that one sister had two days notice before her wedding.
Hammon said girls in the compound were prepared for a similar destiny all their lives, but she knew from a young age she didn't want any part of it.
"It was like marching to the guillotine because I saw pictures of my mother before she got married and she was just so confident.
"Her posture was just excellent and she had a beautiful face and smile... and then I watched her deteriorate after she got married and I watched her go through so much emotional pain and that was what I felt was in store for me if I got married," she said.
Hammon described her father's wives as second-class citizens in the household who became shells of themselves the moment he came into the room. She called it mind control. Her mother had more than two dozen nervous breakdowns, she said.
"I don't know how a woman can allow another woman to come into her home and cook some supper up with the family for her and go to bed with her husband that night and respect herself.
"I don't see how that is possible. You have to let a part of yourself go. A part of something in you, you have to squash that down in order to live with that every day," she said.
It was a fate Hammon escaped with the help of a family she'd been babysitting for outside the compound. About a year after her father died, she asked them if she could stay and they agreed. Hammon says her mother didn't believe she could stop her.
Almost two decades later, the memories of her childhood haunt her. Hammon said she doesn't date much.
"I watched my mom just die emotionally and I relate that to marriage," she said.
Still, she doesn't entirely blame Jeffs for what she went through inside the FLDS community.
"I think that Warren Jeffs is the fall guy for something that has been going on for generations," Hammon said.
"Warren Jeffs is just a person to focus on. This system is a well-oiled machine, there's always going to be somebody to step up and take his place. What he has done is terrible... but I know a lot of other men who were out there and in charge who did some pretty terrible things too. Nobody was paying attention then," she said.
Jeffs was captured August 28, 2006, in a traffic stop near Las Vegas, Nevada. At the time, he had been on the FBI's 10 Most Wanted List for months. E-mail to a friend
CNN's Randi Kaye contributed to this story.