After nine years ad counting with the chart-topping girl group, Jesy Nelson is officially leaving Little Mix.

In a statement posted to Instagram on Monday (December 14), the singer revealed that she is taking time away from the group indefinitely to focus on her mental health.

“The past nine years in Little Mix has been the most incredible time of my life. We have achieved things I never thought possible," the 29-year-old wrote in her exit letter, referencing the group's first Brit Award win and their many sold out shows. "Making friends and fans all over the world I can’t thank you all enough from the bottom of my heart for making me feel like the luckiest girl in the world. You have always been there to support and encourage me and I will never ever forget it."

Unfortunately, being in the band had "taken a toll on [her] mental health."

"I find the constant pressure of being in a girl group and living up to expectations very hard," she wrote. "There comes a time in life when we need to reinvest in taking care of ourselves rather than focusing on making other people happy, and I feel like now is the time to begin that process. So after much consideration and with a heavy heart, I’m announcing I’m leaving Little Mix.”

“I want to say thank you to everyone involved in our journey. All the hard work and dedication that went into making us a success. To every single fan who came to see us in concert, who listened to our songs and sung their hearts out, sent me messages and supported me along the way. I want you to know I love you all so much and I could never have done this without you and I appreciate it endlessly.”

Nelson added that she now plans "to spend some time with the people I love, doing things that make me happy."

She also thanked her bandmates for their support of her decision, as well as their friendship through the years: “Most of all I want to say thank you to Jade, Perrie and Leigh-Anne for creating some of the most amazing memories I’ll never forget. I hope that you’ll continue to fulfill all of your dreams and keep on making music that people love."

The news of Nelson's exit comes just a few weeks after the group’s publicist revealed that Nelson would be taking an extended break for private medical reasons.

On Instagram, the remaining members of Little Mix—Jade Thirlwall, Perrie Edwards and Leigh-Anne Pinnock—wrote a message to their fans in the wake of Nelson's exit, confirming that they will continue on as a trio.

“After an amazing 9 years together Jesy has made the decision to leave Little Mix. This is an incredibly sad time for all of us but we are fully supportive of Jesy. We love her very much and agree that it is so important that she does what is right for her mental health and well-being,” the girl group announced, “We are still very much enjoying our Little Mix journey and the 3 of us are not ready for it to be over. We know that Jesy leaving the group is going to be really upsetting news for our fans. We love you guys so much and are so grateful for your loyalty and continued support of all of us. We’re looking forward to seeing so many of you on tour.”

Little Mix formed in 2011 during the eighth season of The X Factor UK.

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