Astley told the Sun that she shared details of her condition with her first boyfriend, trusting him enough to sleep with him.
He took her trust and cruelly betrayed it, sharing her private information to everyone in her uni dorms.
"Coming back and finding out that people I didn't even know knew was really hard and I was mortified – I couldn't leave my little dorm room for two weeks as I was so upset," Astley told the Sun.
"It was a huge shock especially considering I had opened up to him so much about it."
But Astley says she is now "thankful" because the trauma enabled her to speak openly about her condition.
She now shares details of MRKH on TikTok, talking to her thousands of followers about living with the condition.
Astley said she was that she already been contacted by 15 young women living with the condition and that the experience has made her stronger.
"It's made me a million times stronger as a person to the point I can talk so openly and freely about it," she told the Sun.
Astley isn't the first young woman to go public with the condition.
In 2017, US woman Kaylee Moats launched an online appeal to fund surgery that would allow her to enjoy a full sex life.
Her boyfriend at the time, Robbie Limmer, said he doesn't care about the lack of sex in their relationship but had been putting aside US$50 a month to help fund surgery that would create a vagina.
Her sister then set up a GoFundMe to help Moats reach her goal.
