Singer-songwriter Melanie Martinez, who was a finalist on the third season of The Voice, has responded to sexual assault claims by her former friend and aspiring musician Timothy Heller.

On Monday night, Heller wrote several notes detailing an uncomfortable night with Martinez. Heller said she repeatedly “said no” to Martinez’s sexual advances, and claimed the singer didn’t respect her decision.

“I have kept this secret for years, convincing myself that it wasn’t a big deal and I wasn’t hurt by it,” she wrote. “The thought of accepting that my best friend raped me seems insane. But I began to get responses I wasn’t expecting. Concerned ones.”

Heller said Martinez took advantage of her during her most difficult time, a period where her and Martinez had grown closer together.

“The power she had over me, grew into me having a very hard time saying no to her,” she wrote. “I would do almost anything for her.”

Heller explained that Martinez continued to pursue her while they were sleeping, performing oral sex and using a sex toy without her consent.

“The bottom line that I need to always remind myself is that: I said no. For two nights straight. It doesn’t matter that I didn’t resist during the action. I had been broken down. She knew I didn’t want to, I made that clear. I didn’t scream at her; I didn’t force her off of me. 1) because I loved her. 2) because I just wanted it to all be over,” she wrote.

Martinez tweeted her response a few hours later and denied all sexual assault claims.

"I am horrified and saddened by the statements and story told tonight by Timothy Heller,” Martinez wrote. "What she and I shared was a close friendship for a period of time. We came into each other's lives as we were both starting our careers as artists, and we tried to help each other. We both had pain in dealing with our individual demons and the new paths we were forging, but I truly felt we were trying to lift each other up."