Grey's Anatomy: 5 Times Alex And Izzie Were The Perfect Couple (& 5 Times They Weren't)

Of all the love stories on Grey's Anatomy, it feels like Meredith Grey and Derek Shepherd's is the one for the TV history books. These two meet in a bar, sneak around, deal with the fact that he's married, split up, get back together, become husband and wife via post-it note, start a family, and then he tragically dies. It's a lot.

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But there's another couple who give fans a lot of emotions: Izzie Stevens (Katherine Heigl) and Alex Karev (Justin Chambers). These two aren't together for a very long time, and of course, their romance is filled with obstacles and sad moments. This is Grey's, after all.

10 Perfect: They're Close Pals First

Alex and Izzie are part of the OG friend group on Grey's Anatomy that includes Meredith (Ellen Pompeo), George O'Malley (T.R. Knight), and Cristina Yang (Sandra Oh). They all spend a lot of time together, especially in the first and second seasons, and George and Izzie live in Meredith's house as well.

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It's nice that Alex and Izzie are close friends before becoming anything romantic, and this is one reason why they were the perfect couple. It seemed like they "got" each other, which is something rare. It either happens... or that kind of natural chemistry just isn't there.

9 Not: She's Still Hung Up On Denny

When you fall in love, you can't stop thinking about that person, and sometimes it can even be a bit frustrating. You find your mind wandering during grocery shopping, errands, meetings, and while hanging out with friends or family. You can't help it.

So why does Izzie still think about Denny Duquette (Jeffrey Dean Morgan) even when it seems like she's made the choice to be with Alex? This is something that doesn't seem very logical. If her relationship with Alex was perfect, she wouldn't still be hung up on Denny. Sure, she could miss him and feel terrible about what happened to him, but she would know that choosing Alex was the right thing to do. She seems to be second-guessing things.

8 Perfect: They Come From Similiar Backgrounds

Alex has a very sad family history: his dad wasn't around and he was raised by a single mother who struggled a lot. He and his siblings ended up in the foster system, and that is always difficult and heartbreaking. Izzie was in a trailer park when she was younger, and even had a baby when she was in high school (and decided adoption was the best way to go).

Alex and Izzie were the perfect couple because they come from similar backgrounds. They're not wealthy or privileged, and they know how important it is that they've been given the opportunity of becoming doctors. It's great that they can relate to each other.

7 Not: They Don't Even Plan A Real Wedding

It's true that not every couple is interested in a huge, big, traditional wedding. But shouldn't a couple want to plan their own wedding... and not essentially steal someone else's?

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Izzie and Alex don't seem like the perfect couple because when they get married in the season five episode "What a Difference a Day Makes," they have the wedding that was supposed to be Meredith and Derek's. It feels like a last-minute decision and comes off as confusing rather than romantic.

6 Perfect: Alex Helps Her When She Has Cancer

There are many things that can test a relationship, and when one partner has a serious illness, there needs to be support, love, and understanding. Alex is a total rock star when Izzie gets her cancer diagnosis in the fifth season.

He knows the right things to say all the time, even when she shaves her head and is upset about that. He says she looks gorgeous, and it's a really sweet moment.

5 Not: Alex Is A Player At First

When Alex and Olivia (a nurse played by Sarah Utterback) sleep together, Izzie is really devastated, and it seems like this should be another reason why she and Alex weren't meant to be together.

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Should a perfect couple have such a messy beginning? If they really were soulmates, why didn't they simply jump into a relationship and stay committed to one another? Alex is such a player at the beginning of the series, and it's not attractive. It seems like he can't commit at all.

4 Perfect: They're There For Each Other Even When They're Not Dating

Alex falls in love with a patient named Rebecca Pope (Elizabeth Reaser), who tries to kill herself. Izzie is there for Alex during this difficult time and she's the character who tells him that she needs treatment.

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It's very telling that even when they're not in a relationship, Alex and Izzie can still help each other out and take a deep interest in each other's lives.

3 Not: Denny Is Her One True Love

Izzie loves Denny so much that she literally risks her job (and any future that she has in medicine) by cutting his LVAD wire, which means that he'll be able to get the heart that he's been waiting for. She would never do this for someone that she felt simply lukewarm toward.

It seems possible to view Denny as Izzie's soulmate and one true love, which would make him her perfect person instead of Alex. While Alex and Izzie had a perfectly fine relationship, it didn't hold a candle to the way that she felt about Denny.

2 Perfect: Izzie Allows Alex To Grow Up

When fans meet Alex, he's cocky, self-centered, and seems to treat everyone really badly. He's not marriage material or even someone that people would want to hang out with as co-workers or friends.

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It definitely seems like his relationship with Izzie allows him to grow up, and that's really awesome. Sure, this does mean that in the end, he doesn't want to be with her anymore and he has a newfound love for himself. But this is important for his self-development, and it's interesting to watch.

1 Not: She Totally Ghosts Him

When a couple gets divorced, it can be messy and pretty horrible, but both people tend to follow the legal procedures. Izzie literally bolts and Alex has no clue what has happened to her. It's not a very mature way to end a relationship, let alone a marriage.

Because basically ghosts Alex, that proves that this couple can never be considered perfect. He even talks about never learning what her life was like or where she had moved. That's just plain weird, right? Why would she never talk to anyone at the hospital ever again? She doesn't treat Alex very nicely, which is one reason why his one true love is definitely Jo (Camilla Luddington).

NEXT: 10 TV Couples That Are Always Romanticized (Even Though They're Terrible)

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