Caterina Scorsone, <em>Grey's Anatomy</em> Caterina Scorsone, Grey's Anatomy

All eyes - and hands - are on Meredith (Ellen Pompeo) after she gets attacked by a patient on Thursday's midseason premiere of Grey's Anatomy, but she isn't the only doctor at Grey Sloan who's suffering.

After her relapse in the winter finale, Amelia (Caterina Scorsone) finds herself in a downward spiral. And while Meredith's assault provides a temporary distraction, it also has a lasting impact on the other doctors, Amelia included. "The stress and isolation that led to that drink continue, and [Amelia's] sense of shame and responsibility are definitely triggered with the events that unfold in the premiere episode," Scorsone tells TVGuide.com.

TVGuide.com chatted with Scorsone about what brought Amelia to the brink, and what her drinking means for her and Owen (Kevin McKidd) going forward.

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Amelia made a pretty huge decision by ordering a drink at the bar in the finale. Do you see that as an in-the-moment decision, or was it a long time coming?
Scorsone:
Obviously the year that preceded this point has been really stressful. Losing her brother was a huge, huge blow. He was such a central figure in her life, and so much a part of her identity, her reason for getting up in the morning and striving to be better. So that was really stressful for her. And then, when that episode happened ... I think it was a pretty quick descent and a sudden descent. But I think that it's also important, when you're looking at the disease of addiction, to realize that people who are struggling with that disease really need to be vigilant, because a slip can happen at any time. It can happen to somebody who's thriving and doing really well in their job and having great relationships, but due to stress or a particular loss or being hungry, angry, lonely or tired, which we call HALT, a slip from sobriety is one drink away, and really taking care of yourself and taking care of your relationships is a big part of staying sober.

Speaking of relationships, she had some pretty tough scenes with Owen and Meredith leading up to it.
Scorsone:
Things with Owen are so sensitive and they are dancing around each other a little bit. She thinks things are going really well, and then because of what he's going through, he's treating her in a way that is really confusing for her. And she does feel rejected by him and kind of placed on the outside. Then when Meredith starts to kind of treat her in a rejecting way, she just feels isolated. ... I think her concept of who she is in relation to the people that she cares about in her life is shaken at that moment. ... For her it was just, in this case, the straw that broke the camel's back. I think she felt really on the outside and then she kind of matched her externals to how she was feeling on the inside, and took that drink.

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Amelia and Meredith have had their differences, but Meredith yelling at her in the finale seemed very harsh.
Scorsone:
I think she feels a sense of betrayal, perhaps. In the finale, it really came to a head. Amelia has been trying so hard to establish this familial relationship with Meredith. She moved into the house in order to help with the kids and take some of that burden and really be a sister to her, and I think she really earnestly, and with an open heart, thought that that relationship was important to Meredith too. When she got shut down so harshly, I think it really knocked the wind out of Amelia. I think she was devastated and shocked and embarrassed. She had assumed that the way she felt about Meredith was reciprocated. And so, I think there's just a cocktail of really hard emotions going on for Amelia. I think there's rejection and isolation and embarrassment. ... It was just a perfect storm for her, in terms of tipping her into a bad place.

Riggs (Martin Henderson) clearly has no idea about Amelia's struggles with addiction. But how does Owen react to the fact that his nemesis basically facilitated Amelia's relapse?
Scorsone:
It is a moment until Owen is aware of that situation, but I do think that that'll come into play later on. He doesn't find out about the circumstances of her relapse for a while.

Given Owen's rejection of Amelia and her subsequent relapse, is there any hope for them to have a relationship at this point?
Scorsone:
I think the kind of tragic part of this situation for both of them is that they're so matched in terms of their woundedness, and so far, when one of them has been struggling and having a really hard time, the other one's been able to kind of shore up that broken spot and be a support for the other one. But right now, when this happens, they are both in a pretty fragmented, dark place. She's really struggling, and he is also struggling with some ghosts from his past, and this mysterious situation with his sister. So, neither of them is really in a healthy enough spot to show up for the other one in a way that they would hope to.

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Does there continue to be tension between Amelia and Penny (Samantha Sloyan) going forward, or does Meredith's situation bring them together?
Scorsone:
There's still tension. There are some developments later on, but not at this point. Right when we come back, it's really kind of Meredith-focused. For Amelia, the big relationships that are explored are her relationship with Meredith and her relationship with Owen, and a little bit of her relationship with Richard. But Penny, we're going to wait for that one.

She and Richard (James Pickens Jr.) have bonded over addiction issues before. Does he take her under his wing again?
Scorsone:
He's a person who can speak to her honestly about what's going on. I think he has a deeper understanding of what addiction looks like and how it functions, and he is someone who can kind of cut through that isolation and really make an impact on where she's at.

It seems like Amelia's issues may take a backseat to Meredith's attack on Thursday's episode. Is there anything else you can share about the premiere?
Scorsone:
Buckle up. It's going to be one of those really standout episodes on Grey's Anatomy. I think everybody's going to be shocked to see how it unfolds.

Grey's Anatomy airs Thursdays at 8/7c on ABC.

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