"I was not easy to work with", Lovato says in the documentary, before Nick Jonas chimes in, "And then this episode happened" (referring to the punching, presumably).
It isn't the first time the "Sorry Not Sorry" hitmaker has spoken about the importance of honesty either, as she previously said having a "brutally honest family" helped her "stay grounded" when she was growing up in the spotlight.
With just a week to go until Demi Lovato's documentary "Simply Complicated" is released on YouTube, the songstress has given fans a small glimpse of what they can expect by sharing its official trailer.
"Demi walks up on to the plane".
SA Girl Scouts react to girls being allowed into Boy Scouts
But the new direction is still a big concern for Butler. "I think families have spoken enough that they want it", Hart said. Many scouting organizations in other countries already allow both genders and use gender-free names such as Scouts Canada.
Lovato later said that she dated Jonas for "a month or two". It was this that led the people around her to think she was on a "road to suicide".
In a trip down memory lane, Demi Lovato reminisced about Joe Jonas and pinpointed the exact moment she fell in love with him.
Demi Lovato: Simply Complicated will be released October 17. The singer even admits it's hard to talk about these events on camera.
Plans for the documentary were initially revealed by YouTube in May, when YouTube promised to follow Lovato as she wrote and recorded her latest album, revealing "a year-long personal journey of music reinvention and deep discovery".