Emma Murphy, a 26-year-old fitness blogger from Dublin, Ireland, uploaded a video to her Facebook page after leaving her partner.
In the emotional video, Murphy, who has a visible black eye, talks openly about her violent relationship and how she eventually found the courage to leave with her two young children in tow.
The video has been viewed more than one million times and shared more than 40,000 times (and counting).
She posted the following note with her video: "I thought long and hard before posting this video, this is very difficult for me but I have to do what is RIGHT, if you or anyone you know has it is in a similar situation please share this video to inspire other women around the world, violence is NOT the answer!!!!"
"I’m 26, I’m from Dublin, I have two children. I’ve been in a relationship for three years with a guy who I thought was the love of my life. He was the love of my life," she says with tears in her eyes.
"Last year I found out he cheated on me with one of his clients. I found out in June but he denied it. She contacted me in November and told me she was pregnant. So with the stress I went into labour early, my world was turned upside down.
"You think you know somebody... I loved him so much that I tried to forgive him and I gave him another chance and I took him back. Unfortunately I found out that he did it again."
When Murphy confronted her partner on Friday, she says he punched her in the face.
"And it wasn’t the first time," she says. "Last year he split my head open at an event and prior to that he punched me as well an I had a black eye. And for the last year and a half, I’ve been told that I’m paranoid, I’m a psycho, I’m nuts, my insecurities will kill me one day."
"I finally realised that no, this is not acceptable. No man has the right to put his hand on a woman. No matter how big, how small, no matter where you’re from. It is not right to raise a hand to a woman and it’s only now that I’ve realised that," she says. "I've had the courage to walk away."
She hopes that her video will help other women in domestic violent situations.
Polly Neate, chief executive of Women's Aid, said: "We applaud Emma's bravery - sharing her story on social media has raised a huge amount of awareness.
"The 'mental torture' she describes and the emotional abuse she suffered, as well as her visible physical injuries, convey the complexity of domestic violence, and it is important that this is understood by society - and the reach her story has had will go some way to helping with this.
"Online awareness like this can be empowering and informative, but online spaces can also be a place where threats and abuse happen. Women's Aid research found that almost a third of women who received threats online had them carried out in real life."