This was a surprisingly difficult list to write, not just because there have been an awful lot of couples in Grey's Anatomy over the last 15 years, but also because a lot of those relationships were so perfect that we couldn't really imagine them being with anyone else. Imagine splitting up Meredith and Derek, for example!

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However, despite the medical drama's impressive track record, there have been a few couples that fans weren't exactly too keen about. Other characters have been incredibly unlucky in love and so it's about time that changes. Here are 10 couples that would have made a lot of sense but never got together.

These two were absolutely adorable together and their friendship remains one of the highlights of Grey's Anatomy. This pairing originally started as a one night stand, as Callie was depressed about the deterioration of her relationship with George, who wasn't treating her particularly well.

Mark offered his services to Callie, who accepted, and then felt incredibly guilty afterward. Despite this, though, the two soon became firm friends with benefits, but their relationship never went any further than physical attraction. Mark and Callie were such good friends, that a relationship between the two would have seemed almost natural. They even share a daughter together.

These two became friends after Lexie discovered that George was repeating his intern year and she agreed to keep his secret. As a result, they grew closer and even rented an apartment together, that George christened the 'crapartment', because it was so, you know...less than.

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However, Lexie's constant optimism balanced out George's negativity, and she even helped him realize that things weren't as bad as they seemed. George then became a happier person. Honestly, these two were very cute together and would have made an adorable, awkward little couple.

Many people might be wondering why we've included this entry on the list. To explain, we must refer back to the beginning of Season 14, when it was discovered that Amelia had a benign (but absolutely massive) tumor pressing down on her brain. It was revealed that she had had this tumor for around 10 years.

Struggling to come to terms with what this meant for her, both personally and professionally, Amelia entered a brief spiral of doubt, with DeLuca helping her process everything. Even after her operation, DeLuca was there to comfort her and help her heal. If these two ever became a couple, they would be so supportive of one another.

Izzie and Jackson never really interacted during their time on the show together. Which is fair enough if you think about it, as Izzie left Grey's Anatomy soon after Jackson joined. They didn't even have enough time to become friends. However, we think that if they had been given a chance, they could have made a pretty decent couple.

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Izzie was very cheerful and full of hope, bordering on naive. She always looked out for her patients and advocated for them well but she had a habit of becoming easily attached. When Jackson first arrived, he was arrogant and cocksure. The two could have helped each other to become better surgeons and better people in general.

To a lot of people, the mere fact that Meredith and Alex were even considered to be on this list is the highest form of sacrilege. Be that as it may, Meredith and Alex are now extremely close and have been arguably since before Cristina actually left Grey Sloan Memorial to jet off to Switzerland.

Meredith hasn't really found anyone to be with since Derek died and so it's no exaggeration to say that Alex is probably the most important man in her life. As for Alex himself, he does have Jo, but the way he interacts with Mer makes one think that there could be something between these two best friends. Or maybe it's just wishful thinking.

These two have actually slept together on Grey's Anatomy, but seeing as how Derek is Amelia's big brother, Mark wisely went no further than a casual booty call. However, Mark did date Lexie, who was Derek's little sister-in-law, so really, there is no excuse as to why Amelia and Mark didn't get together beforehand.

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Amelia is known for being a little crazy and that has made her come across as slightly annoying to both characters in, and fans of, Grey's Anatomy. However, I always liked Amelia and she and Mark would have been such a great fit together. They're both hilarious people who can take a joke, but they are also serious, talented professionals.

This is another friendship between two people who should have taken it to the next level. Certainly, in later seasons, Callie and Owen became closer as they went through divorces and disasters and began collaborating on innovative medical projects. They weren't without their disagreements (this is Owen after all) but they always had each other's backs.

In Season 11, they were designing prosthetic limbs to help soldiers who had been injured in the line of duty. Their enthusiasm and teamwork was fun to watch, and they could both have a laugh together. We're sort of glad these two didn't get together, as who knows what would have happened to Callie, but it's fun to imagine what these two would have been like as a couple.

Teddy has been through the mother of all wringers when it comes to her love life. She has loved Owen, who used her as and when he saw fit; the hospital psychologist, whose job meant he couldn't settle down; Henry, who was adorable but died, and Tom, who was dumped for Teddy's baby daddy, Owen.

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Essentially, what we're saying is that, with the exception of Henry, Teddy is too good for all these men. She needs someone who will treat her right and will respect her opinions and choices. Link has already proven that he is a good man and if he weren't with Amelia and a possible baby, we're pretty sure that he and Teddy would make an excellent couple.

Maggie is a great character. She's intelligent, friendly and she gets on well with her colleagues, The one thing that Maggie has always been rubbish at, though, is love. Finding love, being in love, anything to do with love and Maggie the Confident crumbles away into Maggie the Awkward and Obsessed.

However, Tom is the complete opposite. He's casual, very witty and very charming. If he and Maggie got together, Maggie might second doubt everything, as is her MO, but he is probably the only person in Grey Sloan who would encourage Maggie to relax and just have a bit of fun. Maggie would also help to soften Tom and help him to get along with his peers.

We cannot stress this one enough. Despite there being so many strong and confident women in Grey's Anatomy, the only two women Owen Hunt seemingly can't get enough of are Teddy and Amelia. It beggars belief. The worst thing is is that Owen has treated both women terribly in the past and yet they still give him multiple chances.

Owen's relationship with Amelia wasn't all his fault, to be fair, as Amelia kept on backing out 6 or 7 times a day. However, Amelia got better and they resumed their relationship, only for Owen to act like a complete jerk. It was the same with Teddy. Owen only wanted her when she was unavailable and was jealous of any partner she had.

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Ben Pettitt is a recent English graduate of the University of Nottingham. He loves to write, read and watch Netflix. This is one of the reasons why he decided to come and display his knowledge of pop culture as a writer for Screen Rant.

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Grey's Anatomy: 10 Couples That Would Have Made A Lot Of Sense (But Never Got Together) - Screen Rant