Ellen Pompeo is saying goodbye to Grey's Anatomy.

In a heartfelt Instagram post, Pompeo shared her gratitude to fans after 19 seasons of support on the ABC series. "Through it all….none of it …would have been possible without the best fans in the world," she wrote. "You all are RIDERS and you all have made the ride so fun and ICONIC!!" With Pompeo's departure, only two actors from the first season remain -- Chandra Wilson as Dr. Miranda Bailey and James Pickens Jr as Dr. Richard Webber.

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Despite her departure, Pompeo reveals her plans to visit the show, but it's unclear if she will reprise her role as Meredith Grey. "This isn't your first time on the rollercoaster… you know the show must go on and I'll definitely be back to visit. With a lot of love and immense gratitude XoE," she wrote. Since Grey's Anatomy first premiered, many stars have exited the series but guest-starred in select episodes, including Sarah Drew and Kate Walsh.

In 2005, Grey's Anatomy premiered its first season on ABC as a mid-season replacement after Boston Legal's cancellation. As of writing, Grey's Anatomy holds the title for the longest-running scripted primetime show on ABC and became the highest-earning show on television in 2007. The popular series also led to the creation of two spinoffs, Station 19 and Private Practice.

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Since Meredith's acceptance into the residency program at Seattle Grace Hospital, later named Grey Sloan Memorial, she has undergone several major life changes. In Season 8, a plane crash devastated her and other members of the hospital staff. The crash ultimately killed Meredith's half-sister Lexie and Lexie's love interest Mark Sloan. Additionally, a shooter claimed multiple victims at the hospital.

In Season 11, Meredith's husband Derek, played by Patrick Dempsey, died in a car accident. Dempsey cited the reasoning for his departure as scheduling issues. "It's 10 months, 15 hours a day. You never know your schedule," he said. "So your kid asks you, 'What are you doing on Monday?' And you go, 'I don't know,' because I don't know my schedule." Justin Chambers, in hopes of diversifying his acting roles, also left the show after playing Alex Karev for over 15 years. With significant characters like Alex and Meredith out of the picture, it's unclear what direction Grey's Anatomy will head in following the loss of its protagonist.

Source: Instagram