Nate Burrell, star of docuseries 60 Days In, has died aged 33.
His sister Chelsey Walker confirmed his passing to TMZ, revealing he'd taken his own life.
Only a few hours before his death, the former Marine shared a lengthy message on Facebook saying: "I can't keep going on."
"I’m just tired, I’ve been through so much in my life, the pain of my situation now hurts more than I ever imagined. I can’t keep going on."
Nate continued, saying he is "in a much better place" and "no longer fighting the battles that have been causing so much pain in my mind and life".
He added that he appreciates those who tried to make him feel otherwise, but "it doesn't help how I feel".
The reality star said that when he tried to get some help at a hospital for his mental health, he was made to feel "like a criminal".
"Stripped of my dignity and identity and personal property," he wrote.
"I needed my family and friends during this time and you took that away.
“Not being able to communicate put me in such a darker hole than I was in originally that was so hard on me mentally. I would have told you anything to get me out of that place even if it meant I was okay when I wasn’t. You didn’t help me you held me prisoner so I couldn’t hurt myself?"
60 Days In saw Nate and eight others attempt to uncover the injustices done to inmates behind bars. Under assumed names, the participants would enter jail for two months.
Hi sister Chelsey said of the show: "Nathan loved his country, loved his family and was a very caring guy. He was just in a bad place. He was very proud of being on 60 Days In, and he really cherished his time on that show."
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