Little Mix‘s Jesy Nelson has opened up on the exact moment she realised she was going to leave the group.Nelson, who joined the band during their formation on The X Factor in 2011, announced her departure in December.Speaking in a new interview with Cosmopolitan, Nelson explained how being in the group had adversely affected her mental health.Nelson said that her decision to leave Little Mix was made after she suffered a panic attack while filming the music video for ‘Sweet Melody’.“I