Mel C was sexually assaulted the night before the first live Spice Girls performance. Here's why she's talking about it now.

The Spice Girls's Melanie Chisholm (better known as Mel C or Sporty Spice) has penned a new memoir, The Sporty One: My Life as a Spice Girl, in which she writes about having been sexually assaulted by a massage therapist in Istanbul, Turkey, on the night before the group's first live performance in the ’90s.

"It happened to me on the night before the first ever Spice Girls live performance. And we'd never done a full-length concert before, so, obviously, we'd rehearsed for weeks ahead — costume fittings, make-up, hair — everything was leading towards the pinnacle of everything I'd ever wanted to do and ever wanted to be," Chisholm, now 48, said when asked about the incident on Tuesday's episode of the How to Fail with Elizabeth Day podcast. "And what drives me is being onstage, being a performer, so here we were the eve of the first ever Spice Girls show, so I treat myself to a massage in the hotel. And what happened to me, I kind of buried immediately, because there was other things to focus on. You know, I didn't want to make a fuss, but also I didn't have time to deal with it. And because I didn't deal with it at the time, I realize that I allowed that to be buried for years and years and years."

She explained that the assault wasn't initially going to be part of her book, but she realized that she had to share it in order to deal with what happened.

"When I was writing the book, it came to me in a dream, or I kind of woke up and it was in my mind. And I was like, 'Oh my gosh, I haven't even thought about having that in the book,'" Chisholm said. "Then, of course, I had to think, 'Well, do I want to? Do I want to reveal this?' And I just thought, 'Actually, I think it's really important for me to say it and to finally deal with it and process it."

So it was "cathartic" for her, but the singer also wanted to help others who had experienced something similar.

"I suppose in a version of sexual assault, it's a mild version, you know, but I felt violated. I felt very vulnerable. I felt embarrassed, you know, and then I felt unsure, 'Have I got this right, what's going on?'" Chisholm said. "I was in an environment where you take your clothes off with this professional person. So there were so many thoughts and feelings, and I just thought, you know what, I do want to talk about it, because It has affected me."

As the host of the show noted, many sexual assault victims end up questioning themselves after an attack.

Chisholm connected it to the fact that she had been a people-pleaser.

"Everybody knows better than me. What if I'm wrong? I don't want to look stupid. I don't want to be stupid," Chisholm said she thought at the time. "As I've searched my soul, as I've got older and tried to overcome so many things in that … trust your instinct. There's only one person on this planet who knows what is best for you, and that's you. Who knows what is right for you. Even if it wasn't that person's intention, it made you feel that way. And you have to let them know."

The singer is expected to reunite with all four of her former bandmates for a documentary next year.