Little Mix sought therapy together as a group after the departure of Jesy Nelson from the band.
Perrie Edwards told BuzzFeed during an interview to promote their new album that the song Cut You Off came about because of an idea sparked during therapy.
"We actually went to therapy as a group, which we think is really, really helpful," she said.
Edwards added: "We got told to envision the people that are negative in our lives and the people who don't make us feel very good about ourselves.
"And we imagined big scissors to cut people off — and then Jade came up with the concept to make it into a song, which I thought was really freaking cool."
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Edwards said the song is about "someone who's really toxic in your life and you don't want anymore" and that they "really needed" the therapy to communicate and understand that idea.
"We had it individually, we have it as a group as well, which is amazing. So we can all be there together and cry together. It's really nice," the star added.
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Little Mix's new album — the first since they became a trio — is entitled Between Us and also serves as a celebration of the group's 10th anniversary.
It's a greatest hits record, including songs like Black Magic and Wings, but also features five new tracks.
Little Mix formed when all four original members auditioned separately for the eighth series of The X Factor in 2011, going on to become the first group to win the show.
Reflecting on their talent show experience a decade later, Jade Thirlwall said programmes like that "were very much entertainment shows" and they tried to counter some of that with their own show The Search.
Read more: Where are the X Factor winners now?
She added: "I think the shows like [The X Factor], and how they were run, probably couldn't exist anymore.
"It's a hard balance, because obviously we knew what that experience was, but at the same time, we'll always be grateful to that show because it did literally give us the platform and it was on the show [that we] formed together."
It was announced earlier this year that there are no current plans for The X Factor to return to TV screens, with its most recent series airing in 2018.
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