While romance is a huge part of Grey's Anatomy, there have been plenty of times where the surgeons have crossed the line in the name of 'love'

Relationships on the hit ABC medical drama Grey's Anatomy have always been complicated, reflecting a myriad complexities that human beings face in daily life. Whether falling in and out of love, holding a candle for someone who's beyond reach, as well as the dark, murky side of relationships, Grey's has shown it all.

The characters in this series, which is as much a relationship drama as it is medical, have been deeply in love but they have also cheated on their partners and been unfaithful at various times. Some of these creative decisions completely threw the arc while a few made some sense in the broader context.

Updated Nov 5th, 2021 by Kayleigh Banks: From what fans have seen from season 18, most of the characters are quite content with their lives. Owen and Teddy finally tied the knot, Jo seems to have finally moved on from Alex, and Meredith may have found love again with the transplant surgeon, Nick Marsh. But how long will this bliss last? If fans know the writers, it won't be long before they add a surprising twist or love triangle to the mix. Many fans could certainly see one blossoming between Nick, Meredith, and Hayes - but if this proves to be the case, hopefully, it will have a better outcome than some of the previous romances on the show.      

13 Owen Hunt On Emma Marling

Although fans would hate to see some of their favorite characters be unhappy, that does not mean that they completely agree with their actions. There were plenty of fans who didn't agree with the way Owen and Emma's relationship ended as Owen cheated on her after having a one-night stand with Cristina.

From the fans' perspective, this didn't make a lot of sense. Cristina and Owen had already agreed that they didn't belong together anymore since they wanted completely different things in life so no one could understand why the writers were revisiting this storyline. What was even more frustrating was that Owen and Emma seemed quite happy together. It just felt like they were trying to find a way of getting rid of Emma quickly.

12 Alex Karev On Izzie Stevens

At the beginning of Grey's Anatomy, Alex Karev was an arrogant and selfish jerk, who grossly lacked any social etiquette. It was no surprise, then, that he ended up cheating on Izzie Stevens with the nurse Olivia after he let the pressures of the relationship get to him.

Although Izzie and Alex weren't formally together at the time, they were building to something good. Izzie was also the person who convinced everyone to give Alex a second chance after she saw a softer and more vulnerable side to him. In that light, the fact that Alex fooled around with other women while giving Izzie hope, was not cool.

11 Nathan Riggs On Megan Hunt

Nathan Riggs appeared only for rather a short time at Grey Sloan Memorial. He was an ex-colleague of Owen Hunt's at the military, and the fiancé of Owen's sister, Megan.

Megan and Nathan were both revealed to have cheated on each other. But Megan's side of the story was never really shown explicitly, while Nathan was berated time and again by Owen for having cheated on his sister. He was even revealed to have gifted Megan a necklace belonging to the woman he had cheated with. Although he did move heaven and earth for Megan after she was found alive, his history of cheating couldn't be erased.

10 Addison Montgomery On Derek Shepherd

Kate Walsh joined the medical drama as Derek's wife, bringing up the third angle of the love triangle that Meredith and Derek found themselves in. But even as the thorn in Meredith's flesh, Addison soon went on to be a beloved character and fans couldn't get enough of her.

Addison was said to have cheated on Derek with his best friend Mark Sloan prior to the timeline of the show itself. She then came to Seattle to put things right with Derek. However, their marriage was soon cut short when Derek cheated on her with Meredith. Of course, had Addison never cheated, the entire MerDer storyline might never have happened, but keeping that aside, it was pretty low of her to have an affair with her husband's best friend.

9 Derek Shepherd On Addison Montgomery

If there were any fans who had actually thought that Addison and Derek could salvage their marriage, they soon lost all hope once Derek cheated on Addison. It shouldn't have come as a great surprise to people since it was quite evident that Derek was still in love with Meredith. However, instead of telling Addison that their relationship just wasn't working for him anymore, he ended up sleeping with Meredith in the on-call room.

While many MerDer fans were ecstatic to see that their favorite couple were on the verge of reuniting, they didn't like the thought of Addison getting hurt. Considering that Derek knew how it felt to be cheated on, many did think that this wouldn't be a path he would go down. It was just a bit hypocritical considering everything they had been through.

8 Owen Hunt On Cristina Yang

Owen proclaimed his love for Cristina more than once and he did indeed love her, choosing her over Teddy - who he had always had feelings for.

But when Cristina decided not to have children and then had an abortion, the latter decided to hurt her by cheating. He hooked up with a friend of a patient, and later on, he has a long, traumatizing conversation about his unfaithfulness with Cristina. Seeing that Owen and Cristina were the second lead pair for a long time on the show, Owen's indiscretion was indeed disheartening.

7 Ellis Grey On Thatcher Grey

One major case of infidelity happened before the series had started, but continues to have a big impact, even today. Meredith's mom Ellis, had had a long-drawn-out affair with Richard Webber, even though she was married to Thatcher Grey.

Ellis and Richard were in love, but their relationship destroyed Meredith's childhood and her relationship with her biological father, Thatcher. Moreover, Maggie Pierce turned out to be Ellis and Richard's daughter. Although the revelation shocked everyone, it was nice to see Meredith discover she had more family.

6 Richard Webber On Adele

If Ellis cheated on Thatcher then naturally Richard cheated on Adele too. While the two did seem happy together, it wasn't long before the viewers could see how much Richard's infidelity had hurt Adele since she later accused Bailey of having an affair with her husband because he was spending a lot of nights at the hospital.

Considering how sweet and kind Adele was, fans hated to see her hurting. Luckily, the two managed to repair their relationship in the end but there was a time where some fans believed that Adele deserved better.

5 Arizona Robbins On Callie Torres

Callie and Arizona were a lovely couple and fans rooted for them through all the ups and downs. From Callie's accident while she was pregnant to Arizona having her leg amputated after the devastating plane crash, these two had indeed been through a lot.

But what didn't make sense was Arizona cheating on Callie with the craniofacial surgeon Lauren Boswell. While Arizona did struggle in the aftermath of the plane crash, some fans couldn't understand what made her cheat. It really devastated fans that this well-loved couple split up and couldn't make it work in the end. Maybe the Grey's Anatomy writers could create a spinoff for the two so fans could see where they ended up?

4 Teddy Altman On Owen Hunt

Another cheating scandal that occurred in Grey-Sloan has to be Teddy cheating on Owen with Tom Koracick. The usually cool-headed, rational Teddy suddenly decided to throw all caution to the wind when she began a physical relationship with Tom, whom she was casually hooking up with before Owen proposed to her.

Teddy's uncharacteristic behavior did have fans in an uproar - especially since she didn't have any intention of rekindling her relationship with Tom and still wanted to marry Owen. While fans understood that Teddy was confused, they just thought it was a little unfair that she wasn't being honest and giving Tom false hope. Everyone involved in this situation deserved better.

3 Alex Karev On Jo Wilson

With news that Justin Chambers was departing Grey's Anatomy in season 16, many fans had begun to speculate how the writers would close his story. However, out of all the outcomes and theories they came up with, no one would have predicted what the writers came up with. It turns out that Alex had left and was moving to Kansas to be with Izzie and his children.

While many Alex and Izzie fans rejoiced at the news, there was a large backlash from the other part of the community as they thought it was out of character and not fitting. This was mainly due to the fact that Alex was married to Jo and they had been building a future together. Even through their issues, Alex and Jo never gave up on their relationship because they really did bring out the best in one another. Therefore, for him to just leave Jo and outright avoid her made no sense and ultimately undermined Alex's character development.

2 Derek Shepherd On Meredith Grey

Arguably one of the worst betrayals on Grey's Anatomy has been Derek's moment with his research fellow, Renee. In seasons 10 and 11, Meredith's dream relationship with Derek went through a rough patch as the latter left for DC.

Meredith feared the worst and she was almost right, for Derek did end up kissing Renee - although it's possible this kiss opened his eyes and drove away any confusion he might have had regarding him and Meredith. He did come running back to Seattle, but for MerDer shippers, his little moment with his Research Fellow was devastating. Of course, Derek did fall for Meredith while he was still married to Addison, but to see him on the verge of cheating on Meredith herself never went down well with fans.

1 George O'Malley On Callie Torres

George was goofy, adorable, and good through and through, so his sudden decision to cheat on Callie and sleep with Izzie seemed bizarre. True, he and Callie weren't exactly the perfect couple, but that didn't seem to justify the story arc where he acted on his impulses with Izzie - especially since they hadn't really expressed an attraction to one another. The fact that Callie was also quite likable made this storyline all the more frustrating.

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