(NEW YORK) -- Demi Lovato is heartbroken. Her friend Thomas passed away on Tuesday from a suspected overdose.
Lovato, who struggled with substance abuse in the past, posted a heartfelt tribute on her Instagram Stories on Wednesday.
"Please hold your loved ones tight. Tell them they are special and that you love them," she begs in her Instagram Story, where she shared the black and white photo of her late friend.
She then cautions fans "Addiction is NO joke" and called it a "terrible disease."
The 27-year-old also encouraged fans to watch out for their friends and family, "If you or someone you know is struggling please know it's okay to ask for help."
Lovato suffered a near-fatal overdose on July 24, 2018 -- almost a month after revealing she relapsed after six years of sobriety. She addressed fans a month later by writing, "What I’ve learned is that this illness is not something that disappears or fades with time. It is something I must continue to overcome and have not done yet."
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