Grey's Anatomy has come back with season 19, bringing back some old faces along with the new. And while the canvas is still blank when it comes to the new residents, it's exciting to think about the countless possibilities. Because if there is one thing Grey's excels at, it's building relationships that fans love.

After Cristina left, fans were sure no friendship would ever come close to the one she shared with Meredith. And yet they were mistaken because there is solid evidence that the friendship between Alex and Meredith was just as good, if not even better.

"Yang Left Me Her Shares & Her Board Seat & She Left Me You, Too."

Alex Karev (Season 11, Episode 1)

Image of Alex Karev in Grey's Anatomy

Cristina Yang's exit from Grey's Anatomy left a huge void, especially because she was Meredith's best friend and person. Even though Alex and Meredith were already really close, Alex took that as a sign that he had to keep an eye on Meredith, and took his duty very seriously.

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In a heartwarming quote, he admits to Meredith that Cristina left him her shares of the hospital and the seat on the board, but she also left him Meredith. The truth was that while it took Cristina leaving for their friendship to get stronger, they were always meant to be each other's persons.

"... You Earned The Right To Pick And Choose Whoever You Want To Let In."

Alex Karev (Season 15, Episode 3)

An image of Alex Karev talking to Meredith

Full quote: "With Everything And Everyone You Lost In Your Life, You Earned The Right To Pick And Choose Whoever You Want To Let In."

One of the reasons this friendship is so great and a fan-favorite on Grey's Anatomy is that they have known each other since the beginning. Meredith knew Alex back when he was a jerk, and he knew her when she was all "dark and twisty." He saw the things she went through, and that is why he's qualified to speak about it.

When Meredith is complaining about being called closed-off, and admitting that she is at times, he reassures her that she's earned the right to not let everyone in. It's a quote that shows just how deep his respect and understanding of Meredith is.

"People Are What Matters. Alex Is One Of Our People ..."

Meredith Grey (Season 3, Episode 18)

Full quote: "... We Can't Just Leave Him Out In The Cold."

Even back when Alex was still sometimes unpleasant to be around, Meredith saw something more in him. Sure, he was arrogant to nurses and he cheated on Izzie, but he was still part of their intern class and to Meredith that meant something.

Maybe she saw the potential in Alex, or maybe she was going on blind faith, but she didn't abandon him when everybody else did, and that was a clear sign that she cared about him.

"Meredith Always Makes Me Think Screwed Up People Have A Chance."

Alex Karev (Season 3, Episode 17)

An image of Alex Karev wearing his blue scrubs in Grey's Anatomy

One of the things that always held Alex Karev back was his low self-esteem. He hid it behind walls of arrogance and rudeness, but deep down he was bluffing his way through life, trying to convince himself he deserves to be there. It was why he always had problems with his relationships, and why he made stupid mistakes that pushed other people away.

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And it took something extraordinary for him to let go of that image. It took someone who saw past his facade, saw him for everything he was and decided to love him anyway. Meredith was that person for Alex, and even seasons back, she made him think maybe he has a chance, despite being screwed up.

"I Will Go Down Swinging For You, Alex..."

Meredith Grey (Season 13, Episode 9)

Alex telling Meredith about beating DeLuca

Full quote: "... You Know I Will. But That Means You Can't Give Up."

Grey's Anatomy has a great way of bringing back the audience with their storylines and Alex's trouble with the law was one of the biggest plots of the season. Watching it slowly unravel was painful for the audience. Alex was finally facing some real consequences for one of his actions, and it could have been what ruined his career and even his life.

But there was one person who never doubted him, and never turned her back on him. Meredith straight up told Alex that she would go down swinging for him. Of course that made his decision to protect Jo even more painful, because even in his worst moments he tried to be selfless for the woman he loved.

"I Want Waffle Sundays."

Alex Karev (Season 13, Episode 6)

Meredith stands in shock as she sees Penny; Alex is behind her

This was such a loaded moment, because Alex thought he would be going away to jail and his wishes in this scene say a lot about the kind of person he is. And what it tells the audience is that he considers Meredith his family, so he wants to spend as much time with her as he can.

The scene reads almost as if he's saying goodbye to Meredith, and it has some interesting parallels to Cristina's speech in her finale episode. But the bottom point of this is that Meredith is Alex's family, and he sees her in every version of his future. It's scenes likes these that make Grey's one of the best medical dramas streaming today.

"Where Is He? I'll Kill Him. Did He Hurt You? Are You Hurt?"

Alex Karev (Season 12, Episode 16)

Alex and Meredith have a drink at Emerald City Bar in Grey's Anatomy

Alex's protective nature is only one of the reasons fans loved him so much. Meredith was the person he was most protective of because he's seen firsthand what she's been through in life. And the amount of trauma she has been through has literally become one of Grey's Anatomy's plot holes.

This scene might have been intended as funny, placed when he comes to the house after Meredith sleeps with a guy for the first time after Derek's death. However, it truly showcased the kind of guy Alex became, and just what he was willing to do for the people he loved.

"But You Do."

Meredith Grey (Season 11, Episode 1)

Alex hugging Meredith after her assault Grey's Anatomy

Even though Alex said he didn't know what she meant when Meredith called him her person, Meredith knew for a fact that he did. Alex has been her person for a while, even while Cristina was still there. And when Alex hesitantly offers his shoulder to cry on or "whatever," Meredith reassures him with this quote.

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The way Alex said it, it almost felt like he was trying not to overstep, and with these three tiny words, Meredith tells him that he already knows how to be her person, because it didn't take Cristina leaving for him to take over the role.

"Look, She Stood By Me For Years When Everybody Else Left, No Matter What."

Alex Karev (Season 12, Episode 8)

Alex and Meredith in a car looking in the same direction in Grey's Anatomy

Alex is loyal to a fault, and this becomes very obvious when Meredith becomes a problem in his relationship with Jo. When Jo accuses him of always taking Mer's side, he tells her that she was the only one there for him for years, when everybody else left.

Even though it hurts Jo to hear it, Alex doesn't retract his original statement. Because there was a time when everybody left, and Alex is very aware of who stayed.

"Alex Is My … He's My Alex ..."

Meredith Grey (Season 14, Episode 24)

Meredith reading alex's letter

Full quote: "... I Just Got Happy In A World Without Cristina & Without Derek, And I Don't Want To Be Alone."

Alex played a big part of Meredith's journey to happiness after suffering the huge loss of not only her best friend moving across the world, but also having to grieve for her husband while simultaneously being pregnant with his child.

But Alex didn't let that stop him. He knew Meredith's tactic of pushing people away and he stayed anyway. This is a wonderful scene in which Meredith embraced her vulnerability and admits she doesn't want to lose him. It's a poignant moment where she shares just how important he is to her.

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