Sia shared her previously private medical struggles with fans in a Twitter post on Friday, October 4.

"Hey, I'm suffering with chronic pain, a neurological disease, [and] Ehlers Danlos and I just wanted to say to those of you suffering from pain, whether physical or emotional, I love you, keep going," the mysterious pop songstress wrote. "Life is f--king hard. Pain is demoralizing, and you're not alone."

Ehlers-Danlos is a connective tissue disorder that comes in numerous forms. Sia has not revealed which of the thirteen types of the disorder she suffers from. Fans were quick to offer their love, support and even some of their own personal stories of chronic pain, to her.

In a 2013 interview with Billboard, Sia revealed that she struggled with substance abuse. "I got seriously addicted to Vicodin and Oxycodone, and I was always a drinker but I didn't know I was an alcoholic," she shared.

It wasn't until doctors corrected a previous misdiagnosis to hyperthyroid disease that her medicine was changed and she became sober. Last year, the "Chandelier" singer posted that she was celebrating eight years of sobriety.

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