Demi Lovato has suggested her relationship with Wilmer Valderrama was "not OK"

With Demi as the guest on her Baby, This Is Keke Palmer podcast, the 32-year-old host said: "I feel like people don't understand that that's what we was dealing with, you know? I found myself dating. I'm 15. Why is my boyfriend 20?"

Demi replied: "Why was my boyfriend 30? You know what I'm saying?

"But then you look back in hindsight. When I turned 30, I was like, that's not OK."

Keke said: "Girl, the moment when you realise, and you get [to] the age of a lot of people that were around you and doing stuff, it's almost a mental break that can happen because you realise you were taken advantage of. 'Oh, I was being exploited.'

"That was very difficult for me 'cause at 15 I'm thinking my boyfriend's older because I'm doing an older job, and I'm doing a bunch of things, and this is the way that it is, and it seemed normal in my mind."

Demi agreed: "Especially if you're an older soul, too. Especially if you're mature for your age."

The Burbs star Keke praised Hilary Duff's recent single Mature, in which she reflects on an inappropriate age gap in a relationship.

She said: "I love the Hilary Duff song that came out because it's like, 'Oh s***.' We all had the same damn life."

Demi - who is married to Jordan 'Judes' Lutes - has spoken candidly over the years about her struggles with drug and alcohol addiction, self-harm and an eating disorder, and she thinks she got into "bad stuff" because working from a young age made her determined to behave like an adult in other areas of her life.

She said: "For me I actually was like ... I had this mantra that was like, 'If you're going to work me like an adult, I'm going to party like an adult.' And I got into some bad stuff at a young age and that's when I started self-medicating.

"I wish that, you know, I had stayed more focused.

"Obviously, I think the course of my life would have gone in a different direction, meaning I wouldn't have maybe struggled as much with substances later down the road, but everything happens for a reason.

"I'm sitting here in this state of mind today, like, grateful for everything that I've been through. It was really challenging. There wasn't a lot of time for play, but when I did, I played pretty hard."