The 'Neon Lights' singer - who checked into rehab for addiction issues, an eating disorder and self-harming in 2010 - regrets not taking her parents' advice when she got caught up in the party lifestyle as a teenager and wishes she had been less headstrong.
She told the new issue of Nylon magazine: "My parents tried to control me, but I'd be like, 'Oh really, I'm grounded? Well, I pay the bills.' They did the best they could. And I think that's why a lot of young stars struggle when they're making money or providing for their family.
"My mentality was 'Work hard, play hard.' It was hard to listen to the word 'no.' I wanted to make my own rules. I thought that if I was adult enough to get there, then I could party like an adult. And obviously, I couldn't."
The 21-year-old starlet - who rose to fame on 'Barney & Friends' aged six - is hoping to shed her reputation as a fallen Disney star and hopes people will eventually stop talking about her past issues.
Demi - who is a judge on 'The X Factor' USA - said: "I would like to separate myself from being the girl who overcame her issues, or the Disney chick who ended up in rehab while she was still on Disney. I don't want people to hear my songs on the radio and be like, 'Oh, that's the girl who cut.' "
She is grateful to have helped so many troubled fans, however, and believes they share a special relationship because of her own issues.
The blue-haired singer added: "Now I have probably the best relationship between any artist and their fans, because I have no secrets."