Camila Cabello's departure from Fifth Harmony shocked many Harmonizers. And their breakup has been far from amicable , as they've traded open letters on social media. Given how suddenly the break happened, and given that the group is facing a December deadline on their record contract, the timing could not be worse.So what happened? Billboard writes that "tensions had been festering among the group members for some time as Cabello increasingly voiced her desire to pursue a career outside the group." Apparently, Cabello floated the idea of a hiatus and subsequent return, but the group didn't want to wait out her solo career.Here's how the magazine describes their attempts at reconciliation."'There were multiple attempts at interventions -- from bringing a therapist out on the road 'to help the girls sort out their issues,' says an insider, who claims that all but Cabello participated in sessions with the licensed psychologist, to scheduling a 'come to Jesus' sit-down with Reid, management and the girls for which Cabello was purportedly a no-show. But a source close to Cabello contends that a group meeting with Reid was 'never confirmed' and that previous sit-downs with a therapist would 'historically devolve into a four-against-one scenario, much like the dynamic in the current public battle of statements we are seeing, and were largely unproductive.' Instead, 'Camila felt that the best way to communicate effectively with her bandmates was one-on-one, which she did during the European tour.'"It's difficult to say whether this leak is from Cabello's camp, the record label, or the remaining band members. Whatever the case, we'll surely be hearing and feeling a big push behind Cabello in the coming months. Fifth Harmony doesn't have the penetration of One Direction, but this messy public exit is just the type of non-controversy-controversy that can create an anodyne sort of celebrity. After all, nobody cares how Justin Timberlake departed *NSYNC, but a push out of the nest can help a timid bird to fly.Read the full story behind their breakup here