Wise beyond her years after entering rehab at the age of 18, singer, former Disney star and "The X-Factor" judge opened up to Nylon magazine for her December/January cover issue about how her "work hard, play hard" mentality as a teen in the entertainment industry helped land her in rehab.

"I wanted to make my own rules," Lovato, now 21, told the magazine. "I thought that if I was adult enough to get there, then I could party like an adult. And obviously, I couldn't."

And while one's 21st birthday is typically celebrated with plenty of booze, the recovering addict who struggled with drugs and alcohol from a young age chose to spend her special day doing charity work in Kenya instead, an experience that she has said helped solidify her journey towards recovery.

Now she's got a fourth album out, an upcoming headlining world tour and two roles on two hit FOX shows, including "X-Factor" and "Glee" alongside Naya Rivera, but things weren't always so bright for the singer. While Lovato was the girl who seemingly had it all, best friends with the Jonas Brothers and the star of her own hit Disney show and two original movies, behind-the-scenes, she was spiraling.

"My parents tried to control me, but I'd be like, 'Oh really, I'm grounded? Well, I pay the bills,'" Lovato, who has been working in the business since age 10, told Nylon. "They did the best they could. And I think that's why a lot of young stars struggle when they're making money or providing for their family. My mentality was 'Work hard, play hard.' It was hard to listen to the word 'no.'"

Although she's been very open about her struggles with bipolar disorder, anorexia and self-harm, one issue that the star plans to delve into in her forthcoming memoir is her battles with drugs and alcohol.

"I'm battling with internal thoughts on how honest I should be," Lovato told Entertainment Weekly in a recent interview. "Yes, I've been very honest, but if people really knew how dark and deep my struggles got-not just with my eating disorder but with drugs and alcohol-they'd be really shocked. But I'll most likely end up saying everything. Maybe it'll help other people in the industry who are headed down the wrong path."

Despite her recovery being a large part of her image, as Lovato has stated she'd like to use her story to inspire others, she added to Nylon that she would like to separate herself from "being the girl who overcame her issues, or the Disney chick who ended up in rehab while she was still on Disney."

"I don't want people to hear my songs on the radio and be like, 'Oh, that's the girl who cut herself.' Now I have probably the best relationship between any artist and their fans, because I have no secrets," she said.

A lack of secrets also helped buffer Lovato during Joe Jonas' recent tell-all for Vulture magazine, in which the former Jonas Brothers star opened up about his tumultuous relationship with Lovato that he admitted was part of his brand, claiming that Lovato and Miley Cyrus were the ones to introduce him to marijuana. Lovato's friends and family, as well as former Disney star Dylan Sprouse, called Jonas out for his admissions, while Lovato remained relatively silent save for a since-deleted tweet at Jonas that read, "Love you brother #family/friendsforever."

Click here to see more photos from Demi Lovato's Nylon magazine cover shoot.