"5 years sober today," she wrote. "If you're newly sober, keep at it, it gets so so awesome. YOU CAN DO IT."
Speaking withNightline last year, Sia confessed that her life began spiraling out of control in 2005.
"I was extremely depressed at the time, that was one of my lowest points," she said. "I don’t think I ever would have stopped drinking had I not got hooked on Xanax and OxyContin. I don’t think I was taking them for more than maybe 10 months before I hit rock bottom." By 2010, she began a 10-step program.
The press-shy pop star also briefly referenced her battle with addiction in an interview with NPR, explaining that her hit song "Chandelier" is actually a dark reference to alcoholism. "I wrote that song because there's so many party-girl anthems in pop. And I thought it'd be interesting to do a different take on that," she said. "For some reason... I didn't wanna give it away."
As for her latest hit, FKA Twigs is making headlines with a haunting rendition of Sia's "Elastic Heart" for BBC1.
Sia recently teamed up with Gym Class Heroes' Travie McCoy on his super catchy new single, "Golden." He dished on the pair's "brotherly-sisterly vibes" in an interview with ETonline earlier this year. Check it out in the video below.