The singer, 32, who collaborated with Kelly in 2013 recording duet “Do What U Want (With My Body)”, broke her silence on Wednesday night in the midst of the abuse allegations around the musician.
Gaga also vowed to have the track removed from iTunes and all streaming services.
Kelly, 52, has recently come under intense scrutiny in the wake of the Lifetime docuseries, Surviving R. Kelly, that features interviews with women who claim that for decades the hit-making singer and producer used his power and influence to sexually and physically abuse women and young girls.
“I stand behind these women 1000%, believe them, know they are suffering and in pain, and feel strongly that their voices should be heard and taken seriously,” Gaga began the post on her Instagram Stories. “What I am hearing about the allegations against R Kelly is absolutely horrifying and indefensible.”
Gaga, who was sexually assaulted at age 19, went on to explain that the controversial song came during a challenging time in her life.
“As a victim of sexual assault myself, I made both the song and video at a dark time in my life, my intention was to create something extremely defiant and provocative because I was angry and still hadn’t processed the trauma that had occurred in my own life,” she explained of her collaboration with Kelly.
“The song is called ‘Do What U Want (With My Body)’, I think it’s clear how explicitly twisted my thinking was at the time,” Gaga added.
“If I could go back and have a talk with my younger self I’d tell her to go through the therapy I have since then, so that I could understand the confused post-traumatic state that I was in — or if therapy was not available to me or anyone in my situation — to seek help, and speak as openly and honestly as possible about what we’ve been through,” she explained.
“I can’t go back, but I can go forward and continue to support women, men and people of all sexual identities, and of all races, who are victims of sexual assault.”
“I have demonstrated stance on this issue and others many times throughout my career. I share this not to make excuses for myself, but to explain. Til it happens to you, you don’t know how it feels. But I do know how I feel now,” Gaga said, before revealing how she planned to move forward.
“I intend to remove the song off of iTunes and other streaming platforms and will not be working with him again,” she explained. “I’m sorry, both for my poor judgement when I was young, and for not speaking out sooner. I love you.”
Gaga also shared the post on her Twitter captioning it, “I stand by anyone who has ever been the victim of sexual assault.”
Other stars have also spoken out about the allegations, including Meek Mill, Chance the Rapper, Ne-Yo and John Legend.
Legend — who is one of the only stars to speak out in the six-part docuseries on Lifetime — used Twitter ahead of the program’s debut to respond to fans who labeled him as brave for criticizing the “Ignition” singer.
“To everyone telling me how courageous I am for appearing in the doc, it didn’t feel risky at all,” wrote Legend, 40. “I believe these women and don’t give a f— about protecting a serial child rapist. Easy decision.”
Representatives for Kelly, born Robert Sylvester Kelly, responded “no comment” to PEOPLE’s request for a response to the allegations made in Surviving R. Kelly and interviews with alleged victims in this week’s issue of PEOPLE, on newsstands now.
“No one else knew. It was almost like I tried to erase it from my brain. And when it finally came out, it was like a big, ugly monster. And you have to face the monster to heal,” said Gaga, who first disclosed her rape during an interview with Howard Stern in 2014.
The Grammy winner also detailed how she suffers from post-traumatic stress disorder (PTSD) and the symptoms she continues to combat.
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“For me, with my mental health issues, half of the battle in the beginning was, I felt like I was lying to the world because I was feeling so much pain but nobody knew,” she said. “So that’s why I came out and said that I have PTSD, because I don’t want to hide — any more than I already have to.”
Gaga further described, “I feel stunned. Or stunted. You know that feeling when you’re on a roller coaster and you’re just about to go down the really steep slope? That fear and the drop in your stomach? My diaphragm seizes up. Then I have a hard time breathing, and my whole body goes into a spasm.”
“And I begin to cry,” she added. “That’s what it feels like for trauma victims every day, and it’s… miserable. I always say that trauma has a brain. And it works its way into everything that you do.”