Fifth Harmony underwent "many therapy sessions" following Camila Cabello's exit.

The girl group hit headlines in December (16) when Camila made the shocking decision to leave the band. And while both Camila and her former bandmates have since moved on from the controversy, the remaining members have opened up about just how they coped in a new interview with Billboard magazine.

Ally Brooke told the publication there were "many therapy sessions" following Camila's departure, while Lauren Jauregui admitted she was concerned about how Fifth Harmony would survive without their fifth member.

"We'd put blood, sweat and tears - and birthdays and funerals we missed - into this thing," she mused. "It's our livelihoods and our families. This is the train, and now you're like, 'Is the conductor going to come through with the coals, or are we left here to die?'"

But despite the emotionally draining experience of losing a member, the girls feel safe in the knowledge that they tried everything to make it work with Camila before she eventually decided to leave.

"I get to sleep at night knowing we did everything in our power as friends, bandmates and human beings (to make it work)," Normani Kordei said. Ally added, "You can't change people", before Dinah Jane Hansen concluded: "Let's just say we're in a better place now - there are no secrets in this circle."

And while an array of stars, including Ellen DeGeneres, had put themselves forward to become the new fifth member after Camila's exit, the girls insisted they will never replace their pal.

"The fans are our fifth member," Ally quipped.

In their Billboard piece, other famous faces weighed in on Camila leaving, with Dwayne 'The Rock' Johnson, whose 15-year-old daughter Simone is a close friend of Dinah Jane's, telling the magazine the group are "aspirational to so many young girls around the world."

"Once the drama (of Camila's exit) settles, instead of looking at it as a devastating loss, I look at it as an amazing opportunity for growth," he added.