"After almost 6 loving and wonderful years together, we have decided to end our relationship," the "Confident" singer and That '70s Show alum wrote in a post they shared on their Instagram accounts. "This was an incredibly difficult decision for both of us, but we have realized more than anything that we are better as best friends. We will always be supportive of one another."
"Thank you to everyone who has offered us kindness and support over the years," they continued. "With only love, Wilmer & Demi."
The pair, who met in 2010 when they shot a PSA for Voto Latino at Valderrama's home, kept their romance under wraps when they began dating. But as the years went by, Lovato, 23, opened up about their relationship, revealing how the From Dusk Till Dawn star, 36, supported her during her struggles with bipolar depression and an eating disorder.
"He never takes credit for my sobriety, but I guarantee I wouldn't be alive without him today," she told HuffPost Live in 2015.
The "Stone Cold" singer was still gushing about Valderrama as recently as last month, telling Latina magazine, "I've been blessed enough to have him in my life, and not just as my man, but also my best friend."
Lovato is about to kick off her Future Now tour with Nick Jonas, which is set to run until mid-September.
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