But now she's opening up about something she used to keep out of the spotlight—her love life.

In a recent interview with Arianna Huffington for Thrive Global Podcast with iHeartRadio, Demi opened up about her own relationships, along with her most solid advice for fans.

The singer has had a handful of relationships in the public eye including those with Joe Jonas, Guilherme “Bomba” Vasconcelos, and, most notably Wilmer Valderrama. During their interview, Arianna asked Demi about her long-term relationship with Wilmer, which started when she was only 18—and whether she recommends long-term relationships at an age when "most people are just dating around."

"I think that when you find something that is very special to you, don't deny yourself of the opportunity," Demi told Arianna, "But it is important to remember that you are young and you have a lot of life ahead of you so with that in mind choose your future decisions wisely."

Demi seems to be taking her own dating advice, too. As she revealed in her new documentary Demi Lovato: Simply Complicated, she and Wilmer ended their six-year romance because they decided they were better as friends.

While it was challenging, Demi told Ariana that being single actually helped her focus on her recently released album "Tell Me You Love Me." “Whenever I had downtime, instead of going off and being with my boyfriend or doing anything like that, I would go to the studio, and so I had all this extra time in the studio that great things came out of,” she says.

Still, Demi admits it hasn't been easy to let him go. "I think my heart's always with Wilmer. I think that it was with Wilmer, I think that it is with Wilmer, and I think that it will be. You don't share six years with somebody and not give them a piece of your heart, and vice-versa," she says in Simply Complicated. "I'm pretty sure that I'm not gonna meet anybody that compares to him, but I'm trying to keep an open heart and an open mind when it comes to that."