The teen heartthrob, who is currently dating Twilight's Ashley Greene, said things are fine between him and Lovato.
He told US InStyle magazine: "I always try to be cool and still be friends, but sometimes it's better not to... With Demi, it's been friendly, there hasn't been any drama."
Reflecting on his dating life, the 21-year-old JoBro added: "I've been able to meet some really nice girls and some not-so-nice girls."
Despite previous hopes that Demi, 18, would be able to leave rehab for Thanksgiving, it now seems like that won't happen.
Representatives for Lovato told People.com: "She remains committed first and foremost to her treatment.
"Demi has made tremendous progress to date, but understands that she has more work to do"