It feels like Grey's Anatomy has been on forever, and in a way it has, with its seventeenth season currently airing and over 369 episodes available on streaming. While the premise remains the same all these years later, a lot of characters have come and gone as time has ed.

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When a character leaves the medical drama they are usually faced with two likely fates: death, or a new job so far away, they can never pop in to visit. While some of these departures from the ABC drama have made sense for the characters fans fell in love with, others have missed the mark and left viewers enraged at the way they were written off.

Reject: Lexie Grey & Mark Sloan

Mark and Lexie

Lexie Grey and Mark Sloan were meant to be, but fans never got to see their love pan out due to their tragic endings.

Lexie died as a result of a plane crash, but not before Mark professed his love for her and declared that they were supposed to have a wonderful, happy life together. He died shortly thereafter from injuries sustained from the crash. It was heartbreaking to see fan-favorites leave the show (especially in such morbid fashion), and without ever properly reuniting as a couple.

In Character: Preston Burke

Preston Burke leaving the altar.

After being a main character for the first three seasons of the show, Preston Burke left town on the day of his wedding after leaving his fiancé Cristina Yang at the altar. He briefly reprised his role in Season 10 to offer his ex a job, a plot point that checks out given the potential he saw in her as an intern.

Burke and Cristina never had what it takes to be in it for the long haul, and him realizing that at the altar made perfect sense for how they usually treated their relationship; with spontaneity.

Reject: Derek Shepherd

Meredith saying goodbye to Derek.

Neurosurgeon Derek Shepherd died in the show's eleventh season after being hit by a semi-truck and failing to receive a head CT at the hospital he was taken to. After saving the lives of others that day, doctors could not do the same for him and Meredith had to make the difficult decision to take him off life .

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Having Derek meet a tragic end was unfair to viewers invested in Meredith and Derek's love story. Not only did it mark another loss for Mer, it also meant that she'd surely get a new love interest in future seasons of the show.

In Character: George O'Malley

An image of George O'Malley in Grey's Anatomy

George jumping in front of a bus for a stranger was straight out of Seasons 1 and 2 O'Malley. The selfless, goofy 007 intern his peers grew to love would do anything to protect others, even if he didn't know them.

His decision to the army seemed a little out of the blue, but after his divorce from Callie and failed relationship with Izzie, it made sense he might want to branch out and try something new. While it's unfair that he never got to explore outside of Seattle Grace, his death was true to his character and proved that he had the best heart.

Reject: Izzie Stevens

Izzie Stevens leaving Meredith's house.

After surviving cancer, it just didn't make sense that Izzie would want to throw her marriage and friendships away. She got fired for her mistake in the midst of job cuts, but she had already done far worse (like cutting Denny's L-VAD wire).

Izzie relied on the people she met at Seattle Grace, and for her to just run away with so much as a proper goodbye was upsetting and unfortunate, especially when she sent Alex divorce papers via mail.

In Character: Cristina Yang

Cristina Yang in her last episode before departing Grey-Sloan.

Meredith's BFF and the Cardio God herself Cristina Yang left Grey-Sloan at the end of Season 10. Her exit inspired her infamous, "He is not the sun, you are," speech and left many fans wondering how Meredith would go on without her person.

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As far as Cristina's character arc goes though, her departure made sense. She was destined for bigger and better things, especially Grey-Sloan was a hotspot for dying doctors, and nobody wanted Cristina to meet the same fate as so many of her peers. It was a good thing she got out of there before more tragedy could strike.

Reject: April Kepner

April Kepner saying goodbye to Jackson on Grey's Anatomy

The end of Season 14 saw April and Matthew at the altar once again, only this time actually following through with their nuptials.

Fans were saddened that April was departing the show, and even more upset that she and Jackson never found their way back to one another. Instead, April decided to spend forever with the guy she previously rejected. Jackson and April fans lost hope after her exit, but can maybe look forward to a reunion between the two in Season 17.

In Character: Arizona Robbins

Arizona with her daughter, Sofia.

In the same episode that saw April leaving Seattle behind, Arizona says goodbye to her friends to move across the country to be closer to her (newly single) ex-wife.

Arizona's decision to follow Callie to New York so they could co-parent Sofia together filled fans with joy. It meant that there was hope for an (off-screen) reconciliation between Callie and Arizona. There was nothing that Arizona loved more than her daughter and, at one point, Callie so her big New York move made a lot of sense, even if she would be missed at Grey-Sloan.

Reject: Alex Karev

Alex and Izzie's twins, and Jo reading the letter Alex sent her.

In Season 16, Alex takes a leave from the hospital to seemingly visit his mother. However, it is later revealed he actually went to see Izzie, and their 5-year-old twins he had recently learned about. Instead of saying goodbye, Alex wrote Jo and Meredith letters explaining his absence.

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Alex leaving Jo for Izzie in the same way that Izzie left him was completely out of character, and ignored all of the growth he had in seventeen seasons. Couple that with the fact that he isn't even shown onscreen in his last episode, and it's safe to say that fans were not pleased with the show's handling of Justin Chambers leaving.

In Character: Addison Montgomery

Addison on her own spinoff show, "Private Practice".

Addison entered Grey's as a would-be villain when she showed up at Seattle Grace as Derek Shepherd's estranged wife. She quickly became a fan-favorite, as her presence never really threatened Meredith and Derek's relationship. Instead, she was a mentor to the interns, a friend to Callie, and helped strengthen the relationships between other characters.

It only made sense that Addison should be the lead of her own television show, and that's exactly what happened when the Grey's spin-off, Private Practice was developed. Addison, now in California, got to experience life as an OGBYN and divorcée and still made guest appearances in Seattle. It was the best of both worlds.

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