The “Sober” singer, 25, was found unconscious in her Hollywood Hills, California, home and she was rushed to a Los Angeles hospital. She is currently “stable,” a source close to the singer told PEOPLE.
The actor, in turn, is “shocked,” a source close to the former couple tells PEOPLE.
“He knew she was going through a tough time but he wasn’t prepared for this,” the source says. “He saw her through so many ups and downs and was her rock through some of her darkest moments. To see her back in such a sad and vulnerable place is heartbreaking for him.”
The insider adds Valderrama has “always cared deeply for her and they truly remained friends after they broke up.”
“Demi always hoped they would end up back together in the future,” the source continues. “He’s the love of her life and vice versa.”
The two dated for six years before breaking up in June 2016 in a joint statement on Instagram. In February a source close to the two told PEOPLE they were “super, super close and have a crazy love for each other.”
“They’re extremely close friends but there’s always potential they could give a romantic relationship another try,” the source said.
The insider added that Lovato is “very vocal about the fact that he is the love of her life. A lot of their issues had to do with their age difference, but she’s matured a lot even in the past year or so. At first, it was really fun for her to be single and date around, but now she’s starting to see that the grass isn’t always greener.”
Last fall, Lovato opened up about her relationship with the actor saying she “never loved anybody like I loved Wilmer.”
Lovato’s rep confirmed in a statement to PEOPLE late Tuesday that the singer was in stable condition.
“Demi is awake and with her family who want to express thanks to everyone for the love, prayers and support,” the rep said. “Some of the information being reported is incorrect and they respectfully ask for privacy and not speculation as her health and recovery is the most important thing right now.”
Those close to the “Stone Cold” singer noticed red flags for months. A source told PEOPLE Lovato’s recent activities made it apparent the star was relapsing.
“You could tell when Demi was doing well with her sobriety because she wasn’t hanging out at clubs,” the source said. “She has still very much kept up her work schedule and daily life, but there have definitely been signs that she isn’t doing great with her sobriety.”
Another source close to the situation added, “Things have been a total mess for months. She and her team severed ties, and they played a large part in getting her sober years ago. She hasn’t been in a good place.”
Meanwhile, another insider shares: “Demi was never really clean and sober from all of her demons. She has been fighting depression and anxiety for quite some time — and is still in such a dark place. She was sober for a while, but not completely sober for six years.”
Lovato’s hospitalization also comes four weeks after she revealed she had relapsed after six years of sobriety.
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On June 21, the Grammy nominee released the emotional single, “Sober,” in which she sings: “Mama, I’m so sorry I’m not sober anymore / And daddy please forgive me for the drinks spilled on the floor.”
Lovato has battled addiction, mental illness and disordered eating for years. In 2010, she entered treatment, where she was treated for bipolar disorder, bulimia, self-harm and addiction. She relapsed after she left the treatment center, then entered a sober living facility for a year.
The star has been very candid over the years about her alcohol and drug addictions, most recently opening up about her issues in the YouTube documentary, Simply Complicated.
Meanwhile, in September 2017, Lovato was honored with the “Spirit of Sobriety” award at the Brent Shapiro Foundation for Drug Prevention Summer Spectacular in Beverly Hills.
“Every day is a battle,” she said at the time. “You just have to take it one day at a time, some days are easier than others and some days you forget about drinking and using, but for me, I work on my physical health, which is important, but my mental health as well.”
If you or someone you know is in need of help, please contact the SAMHSA substance abuse helpline at 1-800-662-HELP.