"The Voice" contestant Melanie Martinez late Monday responded to allegations of sexual assault by her "former best friend" Timothy Heller. Earlier on Monday, Heller posted a series of tweets saying she "repeatedly said no" to Martinez’s sexual advances.

"I have kept this secret for years, convincing myself that it wasn't a big deal and I wasn't hurt by it. The thought of accepting that my best friend raped me seems insane," Heller wrote on Twitter. "When faced with a friend who really needed help though, I can honestly say she let me down completely."

Heller said that she decided to break her silence about what happened to her following the recent spate of sexual misconduct allegations that have surfaced against celebrities and other popular figures.

"I beg you to imagine her role in this being a man. Girls can rape girls. Best friends can rape best friends. Friendships does not equal consent. Silence doesn't equal consent. I wish it wasn't so hard for me to convince myself of these things," she added.

Martinez, in her response, said she was "horrified and saddened" by Heller's statement, adding:

"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. She never said no to what we chose to do together. And although we parted ways, I am sending her love and light always."

Heller, an aspiring singer, released her solo debut, "Sleep" in October. She was part of the "Dresses" and performed vocals for the group, along with male vocalist and musician Jared Ryan Maldonado.

In her interview with Atwood Magazine about her single, Heller opened up about her experience with mental illness.

"My experience in Dresses was a lot darker than anyone let on: I was struggling a lot with mental illness, and had an extremely unsupportive team around me. I was subject to a lot of mental abuse, but kept around because they needed my voice for the band… I was so defeated. But a lot of good things came out of my year without making music: I focused more on my mental health than I ever have in my life," she said in October.

Meanwhile, Martinez gained fame after appearing on "The Voice" in 2012 and made it to the final six before being eliminated. In 2015, Martinez’s debut studio album, Cry Baby, debuted at No. 6 on the Billboard 200.

Below are some Twitter reactions to the latest accusation: