Demi Lovato has opened up about her troubled past and continued struggle with bipolar disorder.

The 21-year-old singer and former "The X Factor" judge spoke to Cosmopolitan for Latinas for the magazine's summer issue, and said that managing her bipolar disorder is "a daily thing."

"I treat it with medication," she reveals. "Not everybody does that, but for me it works. That's what works for me -- medicating, checking in with people, being honest and being grateful for things."

Lovato certainly has a lot to be grateful for -- her fourth studio album, Demi, was well-received by critics and fans, and she has performed all around the country on her Neon Lights tour. The tour headed to South America at the end of April, and wraps up in London, England on June 1.

The singer has traveled a long road to her recent success. She was severely bullied as a child, and struggled with bulimia, drug abuse and self-mutilation as a teen. Her troubles continued into adulthood until a three-month rehab stint helped to turn her life around.

"I was used to drinking and doing drugs on my birthday," Lovato admits. "I always imagined my 21st being a huge party where I'd get [expletive]faced and go crazy. But I realized that there's so much more to life than that... We have so much to be grateful for."

"When I was younger, I needed someone in the spotlight to idolize, who stood for positivity and light and happiness, and wanted to change the world," she recalls. "Because I didn't have that, I realized I wanted to do that, if only for my 12-year-old little sister."

Lovato says she is "very proud" of how far she has come, and wants to "make music that will last for decades." The singer currently has a fifth studio album in the works.