Washington (CNN) Evelyn Yang was reading letters that voters had sent to her husband, Democratic presidential candidate Andrew Yang , and suddenly stopped in her tracks.

A woman wrote that she had decided to press sexual assault charges against an investor in her company, because she had heard Yang talk on the campaign trail about how female entrepreneurs don't get enough support.

"That was enough for her to make this life-altering move, and that was just so powerful. I remember reading that letter and others and saying, 'I feel you. I wish I could reach out to you and tell you I understand. I have my own story,'" Evelyn Yang told CNN.

In fact, she says her own story of sexual assault was so secret that she never even shared it with most of her family, including her parents.

But Evelyn Yang says the overwhelming response -- and gratitude from voters -- that she and her husband receive when they talk openly about their son Christopher's autism made her feel newly empowered. So she reached out to CNN to go public for the first time.

"Something about being on the trail and meeting people and seeing the difference that we've been making already has moved me to share my own story about it, about sexual assault," she said.

Like the multiple accusations of sexual assault against Harvey Weinstein and Jeffrey Epstein, Yang's story is one where she says justice was delayed and mostly denied, adding to the pain she and other victims experience even after reporting and sharing their stories. Yang wants to change this.

"Everyone has their own MeToo story. It's far too prevalent," Yang added. "But not everyone can tell their story. Not everyone has the audience or platform to tell their story, and I actually feel like I'm in this very privileged position to be able to do that."

'I knew it was wrong. I knew I was being assaulted.'

It was the beginning of 2012. Yang, pregnant with her first child, had found an obstetrician-gynecologist who had a good reputation and worked at the world-renowned medical facilities at Columbia University. His name was Dr. Robert Hadden.

Initially, she says, she didn't see any red flags, but as the months progressed, Hadden started asking her inappropriate, unsolicited questions about sexual activity with her husband, which were unrelated to her health or the health of her unborn child. Looking back, she now believes he was prepping her for sexual abuse.

"There was absolutely no premise for that line of questioning, and it seemed like he just wanted to hear about me talking about sex. What I kept sticking to was this: 'OK, so my doctor is pervy. I have a pervy doctor, but I'm going to focus on having a healthy baby,' and the idea of changing doctors was overwhelming for me."

Going to the gynecologist is an experience that makes many women feel vulnerable and uncomfortable. Going when pregnant adds an entirely different level of anxiety, especially during a first pregnancy, when a woman may not know what to expect. Yang says Hadden took advantage of that.

"The examinations became longer, more frequent, and I learned that they were unnecessary most of the time," she recalled, but she told herself, "I suppose I just need to trust him."

Yang says Hadden violated that trust in an unthinkable way when she was seven months pregnant.

"I was in the exam room, and I was dressed and ready to go. Then, at the last minute, he kind of made up an excuse. He said something about, 'I think you might need a C-section,' and he proceeded to grab me over to him and undress me and examine me internally, ungloved," she recalled.

"I knew it was wrong. I knew I was being assaulted," she added.

Like so many survivors of sexual assault, Yang said she had always thought she would run away in a situation like this. But that's not what happened.

"I imagined myself as someone being, you know, like I would throw a chair at him and run out yelling bloody murder," Yang said.

"I just kind of froze like a deer in headlights, just frozen. I knew it was happening. I could feel it," she added. "I remember trying to fix my eyes on a spot on the wall and just trying to avoid seeing his face as he was assaulting me, just waiting for it to be over."

Hadden walked out of the room without washing his hands, Yang said. She left his practice and never returned.

In legal filings, Hadden's attorney denied Yang's allegations. The attorney declined CNN's request for an interview.

Yang repeatedly brings up how she blamed herself for a long time.

"I thought there was something I did to invite this kind of behavior," she said.

"I feel like I put up with some inappropriate behavior that I didn't know at the time was straight-up sexual abuse/sexual assault until much later, and I regret having put up with that," she added.

Despite the trauma, and urgently having to find a new doctor to see her through the rest of her pregnancy, Yang didn't tell a soul what had happened to her, not even her husband.

"I didn't tell Andrew or my family because I didn't want to upset them," she said. I thought, 'This happened to me. I can process this. I can deal with it. I can compartmentalize it.'"

She also kept it from her husband because she was worried that he would think it was his fault, since he wasn't with her at the appointments with Hadden. At the time, he was traveling a lot for the nonprofit organization he had started. She says she never asked him to come to her doctor's visits.

"I certainly didn't want Andrew blaming himself for not being able to go with me to these doctor's visits because honestly, if he was with me in the room, if anyone was with me in the room, this obviously wouldn't have happened," she said.

'I wasn't alone'

Many months later, after her son Christopher had been born, a letter came in the mail telling her that Hadden had left his practice.

"I got goosebumps and I thought to myself, what if this has something to do with what happened to me?"

She googled Hadden and found a headline that said another woman alleged he had assaulted her and had reported it to police.

"And at that moment, everything just stood still. It was this sense of relief of finally realizing that I wasn't alone in it," she said, adding that she had instantly stopped blaming herself for what had happened.

"It wasn't something that I did. This was a serial predator and he just picked me as his prey," she said.

Finally, she decided to tell her husband.

"I needed to share it at that moment because it felt so big to me and I needed that support. And I told him, and he cried," Evelyn Yang said.

He told her he remembered her coming home one day ranting about how men should never be allowed to be OB-GYNs.

"He remembered that I had made this comment and he felt so bad. He felt guilty that he didn't make the connection or ask me more," she said. "He felt terrible for me, and I think that's what I was trying to prevent by not telling him in the first place."

In a statement Thursday, Andrew Yang said his "heart breaks" when he thinks about it.

"I'm extraordinarily proud of Evelyn for telling her story, and my heart breaks every time I think of what she had to experience. She is my best friend and the bravest woman I know," Andrew Yang said. "No one deserves to be harmed and treated the way she and countless other women have been. When victims of abuse come forward, they deserve our belief, support, and protection. I hope that Evelyn's story gives strength to those who have suffered and sends a clear message that our institutions must do more to protect and respond to women."

Prosecuted by Manhattan DA's office involved in Epstein and Weinstein cases

Evelyn Yang found a lawyer, who discovered that the Manhattan district attorney's office had an open case against Hadden. Several other women had come forward with similar stories of being assaulted by Hadden while he was their OB-GYN.

"That was just life-changing. I mean, it felt like I wasn't alone, and it felt so good not to be alone in this," she said.

The office of Manhattan District Attorney Cy Vance is the same one that was lenient with Jeffrey Epstein over registering as a sex offender and had initially failed to prosecute Harvey Weinstein after allegations of sexual abuse. Weinstein is now being tried on charges of rape in New York City and has pleaded not guilty.

Yang worked with an assistant district attorney, Laura Millendorf, whose office collected information from 18 female patients of Hadden's -- including Yang -- who accused him of assaulting them. Yang testified before a grand jury, which indicted Hadden on multiple felony sex charges.

Millendorf, Yang said, assured her that they were building a strong case to put Hadden in jail.

Then, she said, she stopped hearing from Millendorf and many months went by with no contact.

In 2016, the Manhattan district attorney's office agreed to a plea deal with Hadden. He pleaded guilty to two of nine charges against him -- one count of forcible touching and one count of third-degree sexual abuse. As part of the deal, Hadden would lose his medical license and register as the lowest-level sex offender, but he would not go to jail.

Yang said Millendorf had trouble hiding her disappointment. "She sounded apologetic. She told me that the deal was made above her head, that she was taken out of the negotiations because she was pushing for jail time," Yang said about Millendorf.

"She sounded like she wasn't in favor of that outcome, but she tried to be positive and sell it to me as well. At least he's off the streets, he's not practicing anymore, he won't be able to do this anymore to anyone else," Yang added.

Millendorf declined to comment, through a city spokesperson.

In a statement to CNN, Vance said: "Dr. Hadden was a serial sexual predator who used access and power to take advantage of women in their most vulnerable states. We support all of his survivors, and applaud their strength and courage. Because a conviction is never a guaranteed outcome in a criminal trial, our primary concern was holding him accountable and making sure he could never do this again -- which is why we insisted on a felony conviction and permanent surrender of his medical license. While we stand by our legal analysis and resulting disposition of this difficult case, we regret that this resolution has caused survivors pain."

Yang added she was also frustrated that she was not given a chance to speak directly to the judge when Hadden was sentenced.

"I was just flat-out denied, other women flat-out denied. And that was very strategic. It was very strategic so that the judge wouldn't be influenced if there were dozens of women in court saying that this man had assaulted them to this degree, maybe the judge would have said, 'Why is he not getting any jail time? Why aren't you pursuing jail time?'"

Women sue Columbia University for alleged cover-up

Hadden had lost his medical license, and Yang said Millendorf had told her she should feel good about her role in making that happen. But Hadden had pleaded guilty to assaulting only two women and Yang was not one of them.

"They said that the punishment was the same regardless ... so it didn't matter," she said. "I thought, 'Well, it matters to me, for obvious reasons.'"

It wasn't until after the #MeToo movement, and the Weinstein case came out, that the victims in this case realized that they had been betrayed twice, said Yang.

"It's like getting slapped in the face and punched in the gut. The DA's office is meant to protect us, is meant to serve justice, and there was no justice here."

Yang also blames Columbia University, which runs the medical facility where Hadden practiced and which she alleges protected him. Six weeks before Yang says she was assaulted in 2012, police went to Hadden's office and arrested him after a patient told police he had licked her vagina during an exam.

Hadden's arrest was voided and he was allowed to return to work. The assault allegation, which led to his arrest, was included in the indictment against him two years later.

"What happened to me should have never happened. He was arrested in his office," Yang said, and was back to work shortly thereafter. "I mean at the very least, the bare minimum would be to make sure that there's an aide all the time, and that's what's very painful is knowing that actually what happened to me could have been prevented."

"Can you imagine the audacity of a man who continues to do this after being arrested? It's like he knew that he wouldn't face any repercussions. That he was protected. That he wouldn't be fired," Yang added.

Yang and 31 other women are now suing Columbia University, its affiliates and Hadden, arguing that they "actively concealed, conspired, and enabled" Hadden's sexual exploitation, which the suit alleges occurred as early as 1992.

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Yang's civil suit details a litany of sexual assault allegations against Hadden including performing multiple unnecessary exams, forcing patients to strip naked, groping their breasts and bodies, digitally penetrating their vaginas and anuses, and "surreptitiously licking countless patients' vaginas."

The suit claims that medical assistants who worked with Hadden knew of his sexual abuse but because of lack of training and a "hidden imbalance of power" they did not intervene, and that Columbia "kept the complaints secret to avoid negative publicity."

In court papers, Hadden has denied the allegations except those in his prior guilty plea.

Columbia and the hospital system have contested the suit on procedural grounds.

In response to detailed questions about the allegations against Columbia, including why Hadden had been allowed to go back to work after his initial arrest, a university spokeswoman said the allegations against Hadden are "abhorrent" and they "deeply apologize to those whose trust was violated."

Evelyn and Andrew Yang both hold degrees from Columbia, adding another layer of pain for the family.

"It's a name-brand university behind this doctor, using their influence to protect themselves at the expense of the victims in the case," Evelyn Yang said.

Why go public now?

Yang fought in court for more than two years to keep her identity anonymous in connection with the legal action against Hadden. First, she said, because she is a private person, and second, because she hadn't told most of her family -- including her parents -- even as she sat down with CNN for the interview.

She also says that Hadden's legal team fought against her being able to stay anonymous in order to try to intimidate her. But her time on the campaign trail, speaking to women, compelled her to come forward.

"My experience with the sexual assault and all that happened afterwards is such a powerful and upsetting example of the truth that women are living with every day. And I just happen to be able to have a platform to talk about it," Yang said.

She realizes that right now, with her husband's bid for president, she has a voice that could make a difference -- both for other survivors of Hadden and for women who have dealt with this more broadly.

"I need to use that voice," she said. "I feel like it's something that's an obligation but also a privilege and a gift that I get to share my story now and also help other women."

Getting to this point has been very draining and difficult for her. Like many survivors of sexual abuse and assault, she says that every time she talks about it she is transported back to what happened, and all the trauma that comes with it.

"It's my high hope for this -- it's to empower myself and to empower other women," said Yang."This is very hard to come out with, but I hope it, and I have to believe, that it's worth it."