Owen Hunt arrives at Seattle Grace Hospital in season five of the hit primetime medical drama, Grey's Anatomy. Before practicing medicine at the hospital, Owen was a surgeon for the United States Army.

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Owen was originally just supposed to be a recurring character on the series for a story-arc, but was made a series regular after his first appearance on the show. In addition to being incredibly smart, Owen is also very charming and very handsome, making him a prime candidate for his single colleagues and giving this doctor more than just a medical storyline on the series.

"I am no good for you."

Owen and Crsitina look at each other Grey's Anatomy

Owen and Cristina's relationship is one of the strongest out of all seventeen seasons of the series thus far. Critics praised Sandra Oh and Kevin McKidd's chemistry, and there are a lot of great moments, both happy and sad, between these two characters.

Early on in the relationship, Owen is suffering from PTSD after spending time in Iraq as a surgeon in the army. Owen wakes up in the middle of the night, choking Cristina while having a nightmare, and he knows he must separate himself from her, or he could hurt her even more. The idea of staying away from her kills Owen.

"I'm saying, 'take care now'."

After Owen chokes Cristina while having a night terror from his PTSD, the two break-up, which makes working together difficult. Owen is distant, and Cristina picks up on it pretty quickly.

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Cristina confronts Owen outside of the hospital after a long shift. Owen tells Cristina that the only three words he can say to her are "take care now" because the other three words that he really wants to say instead, he can't say because they aren't together and can't ever be together.

"There's a billion people out there, but I imagine there's only one her."

Sandra Oh and Kevin McKidd

Cristina and Owen are no longer dating, but still have to work together. Cristina wants to help Owen meet someone new now that their relationship is over, and they can be friends.

She tries to make Owen an online dating profile, but he refuses to participate. Cristina asks Owen what he's looking for in a partner, and he starts listing things. As Owen continues to speak, it's clear he's talking about Cristina, and he knows she is one of a kind.

"I love you so much that it hurts."

Owen has been growing more and more distant with Cristina, and Cristina starts to worry that he's having an affair, even going so far as to accuse a nurse at the hospital of having an affair with her husband.

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When Owen comes home late from work again, Cristina is waiting for them, and they finally have it out. Cristina asks if Owen loves her, and he says he does and that it hurts, and then he admits to having cheated on her.

"I will always be in love with you. You are the love of my life."

Grey's Anatomy Cristina Yang Owen Hunt Wedding

After Owen has an affair, he and Cristina are left figuring out how to navigate their relationship with Owen's infidelity. Cristina wants to know every detail of his interaction with the other woman.

She presses a hesitant Owen until he tells her how and what exactly happened. Once he's done giving her all of the details, a devastated Cristina begins to question everything, but Owen tells her it was just a mistake, and he reminds her how in love with her he really is.

"I know nothing good can come of me asking you to stay. So I'm not."

Owen and Cristina talking at the hospital on Grey's Anatomy

Owen and Cristina's relationship can't survive all the ups and downs, and eventually, Cristina decides to leave Seattle and move to Zurich for a new, dream job. Owen knows he has to let her go.

RELATED: 16 Things Only Trust Fans Know About Cristina Yang

He knows the relationship has run its course, and they can't be together again, so he makes the hardest decision of his life and decides to support Cristina's move. It's Owen's final act of love for his former wife and love of his life.

"We're all a risk. We all have something."

Amelia and Owen on Grey's Anatomy

When Owen first meets Amelia, Derek fills him in on his sister's history. Amelia struggles with addiction and is in recovery, which is a risk factor her colleagues must consider when putting her on cases.

RELATED: Grey's Anatomy: Amelia Shepherd's 10 Most Heartbreaking Moments

Owen is instantly attracted to Amelia, and Amelia reciprocates the feelings, so she goes to Owen herself to explain her history and her outlook on everything. She tells Owen she wanted him to hear it from her, which means a lot to him and seems to intensify the feelings he already had for his new co-worker.

"I love her, and it's exhausting."

AMELIA OWEN MARRIAGE GREYS

After Teddy and Cristina, Owen falls for Amelia Shepherd, a doctor at what is now called Grey Sloane Memorial Hospital and the sister to Derek Shepherd. Amelia and Owen's relationship is a lot for anyone to take on.

They both have a lot of baggage going into their relationship, and there's a lot to work out if they want to be together. Owen turns to Amelia's sister-in-law, Meredith, to vent, professing his love for Amelia, but also how stressful it all can be.

"I do love you! I want you."

Owen looking at Teddy

Owen Hunt and Teddy Altman have been through a lot together. They had a history while serving in the army and rekindle their love once they meet again at Seattle Grace Mercy West hospital after Owen recruits Teddy to be the head of Cardiothoracic Surgery.

The couple is very on-again-off-again throughout the series, and in one scene where they are "on-again," Teddy confronts Owen about their relationship, and he professes his love for her.

"I'm starting a new pattern."

Owen and Teddy welcome their daughter in Grey's Anatomy

In the later seasons, Teddy and Owen have rekindled their love, and this time, Owen won't let Teddy go.  Teddy is pregnant with Owen's child, and Owen proposes.

Initially, Teddy says no, not wanting to repeat a pattern, but Owen tells her that he's proposing to start a new pattern because he loves her, and he wants to marry her. He's not proposing because she's pregnant, that just happens to be a bonus factor to how much he already loves her.

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