Lovato, 21, who had herself sought treatment for drug abuse and other issues in 2010, recently praised Gomez, 21, for checking into a rehab for her hard partying ways, reported E!Online.
"Selena is... I've known her for 14 years and we've been best friends. She's amazing. I love her," Lovato said.
When asked about Gomez's condition, Lovato said, "We're best friends but that's all of her business and I just want to let her do her thing. She's amazing, I love her."