"I tend to get fired up about the things I believe in, and although my heart and intentions are always in the right place.
"Unfortunately sometimes my passion gets the best of me and causes me to say things that I probably shouldn't say," Lovato, 23, wrote on Instagram.
The "Stone Cold" singer urged fans to focus on "the topic of victims of sexual and physical abuse being afraid to come forward with their stories" and that her mission is to see "women coming together and actually making a difference."
Kesha, 28, broke down in tears when a New York Supreme Court judge denied her request for a preliminary injunction that would allow her to record and release music without Dr Luke, who she is also suing for allegedly drugging and raping her.
Luke has denied the "Tik Tok" singer's allegations through his lawyer, Christine Lepera, and countersued for defamation.