This Is Us star Chrissy Metz unpacks saying goodbye to Katoby, Kate's new romance

Warning: This story contains spoilers for Tuesday's episode of This Is Us, titled "Katoby."

The saying goes that as soon as one door closes, somewhere God opens a window...

In the case of Kate's love life on This Is Us, that adage held true in Tuesday night's big divorce episode, "Katoby." As Kate (Chrissy Metz) and Toby's (Chris Sullivan) marriage entered its death throes and eventually dissolved, the divorce proceedings were juxtaposed against the start of a new romance with curmudgeonly music teacher, Phillip (Chris Geere).

Flitting back and forth across time and space, we watched as Katoby's attempts at therapy grew increasingly futile, leading Kate to call time of death on their relationship and initiate a divorce. But cast against this was the start of a friendship with Phillip (karaoke singing "Tubthumping"), their first date, Phillip's marriage proposal, and their engagement party, complete with Sophie (Alexandra Breckinridge) — and Kevin's latest commercial star date — in attendance.

All of this circled around the impending nuptials of Kate and Phillip (which we'll finally see next week), and in particular, a phone call Toby made to Kate on the morning of her wedding. He wasn't calling (thank god!) to make a last ditch attempt to convince her to jilt Phillip and run away with him, but instead to tell her that what she'd told him the day they signed their divorce papers had finally sunk in.

It's not until the end of the episode that we learn what those words are — the idea that their story together isn't over, it's simply taking on a new shape — and Toby's realization that Kate was right all along (maybe more of that line of thinking would've saved their marriage).

We called up Chrissy Metz to get the details behind playing a divorce and a new romance in one episode, what she made of Toby's wedding phone call, and more. Take a break from singing "I Get Knocked Down" and read more below.

ENTERTAINMENT WEEKLY: This episode has two purposes: to both show us the end of Kate and Toby's relationship and the start of Kate and Phillip's. Did you get a bit of emotional whiplash having to go between those two romantic extremes?

CHRISSY METZ: Yes, actually. It's not only just a breakup. It's a new relationship. And we're going back and forth in time because that's the brilliance of the show. And it was 36 changes, multiple times and spans of literally years. It was challenging.

Chris Sullivan has been your screen partner since this thing started, and I know you've said before that the two of you avoided talking about it, that you felt physically ill filming some of the fights. How hard were those true, final breakup scenes, the ones where you officially said it was over and post-signing the papers?

It's much like real relationships, whether they're platonic or romantic. There's so much build up and women process things so differently than men. Kate has processed so much that Toby didn't until the end, and in my own relationships, it typically seems to be that way, that by the time women have processed it they're like, "Okay, I'm ready to go." And the men are like, "Huh? What are you talking about?" It feels that way with Kate and Toby. She'd been feeling this for so long, and they've been trying and trying to salvage it and fix it and patch it back together. It's not easy when you love the person, but you know that you're not supposed to be with them any longer. That's the hardest part, because it's so bittersweet because there's no real anger. If we've exhausted all efforts, then what else can you do? But having those processes as individuals, and then finally coming to a head at the mediation and divorce, it's almost a relief, in a way. It's incredibly sad, but it's been such a long time coming that you're like, "Oh my gosh, we can breathe for a moment," as difficult as it is to shoot, [because] literally you're saying goodbye to a relationship that existed for many, many years.

I'm sure you feel like you can breathe as an actor now, too, that you've cleared that hurdle.

Yes. But also just like in a real relationship, it's bittersweet because so much of what Kate and Toby did for each other is how they go and move into their next relationship. It's still hard when you love the person. But there is a bit of a reprieve. A bit of a breath.

In every single case, divorce is fraught and complex, but what do you think the final nail in the coffin was? Is it is it just a matter that they both changed a lot as people, but not together?

Yeah, that is the overall issue in the relationship, that they weren't seeing eye-to-eye because they weren't growing in the same ways and they wanted different things. The whole point of us living on this plane of existence is to evolve. You see in the episode that they tried counseling for a while, even when he comes back from the park, and he's like, "No, it was great. And I really think we can do this." He still wasn't honoring how she felt. And while it's beautiful that he's still fighting for her — is it that he's fighting for her, or is it his ego? It's so layered. You could go back to when she even told him at the weight loss group that she didn't want to date anybody. She wasn't ready, and he continued to push. For him to say that she fell in love with a character defect, she did. And she had her own. Both character defects and coping mechanisms fell in love with each other, but they weren't healthy and they weren't healed in ways that they needed to be to be the best partner, ultimately.

In Kate's mind, he wasn't honest about him going to the gym and his weight loss. And that was a point of contention. And that he was having this other separate life in San Francisco when she was happy for him. But also she was parenting by herself. All of these things can happen simultaneously. And it's okay that he wants to be happy and it's okay that she wants to be happy, but why should she have to concede to move to San Francisco and choose Toby again? The whole point is that she's never chosen herself. And now that she is, it means a different path for both of them. And that's a tough pill to swallow for a lot of people watching the show.

Well, that scene where Toby basically begs her to take him back and try again. How much of her is tempted to say "yes" in that moment?

A lot. She loves him. That's the hardest part. I know many people, myself included, that have rekindled with somebody that they know they shouldn't be with. You're just prolonging the inevitable because you're afraid to rip off the bandaid. You're like, "But I don't know what the wound looks like, so I'll just cover it back up." It's really special that scene was even written because it's so true to life. Yes, it would be in the moment seemingly easier, a little more comfortable, but in the long run we've already seen this. It's the same fight. It's the same thing over and over. As much as she wanted to stay with him and be with him, she knew that in the long run, it wasn't going to work because it hadn't been working. And they just want different things.

I honestly kind of thought it was a little bit messed up of Toby to call Kate on her wedding day, of all days, to have this conversation. But what did you make of that?

Girl, girl. I said, "He can call back!" When I was reading through the script the first time, I was like, "Oh my God, he's going to call, they're going to get back together." And then I was like, "No, no, they can't get back together." And I thought, "Okay, I'm gonna trust Dan [Fogelman, the show's creator] and Isaac [Aptaker, executive producer] and Elizabeth [Berger, executive producer] and all the writers. It's going to be a beautiful moment." Sure enough, of course it was that. Having so much grace around that very special day for her, and the love that they have for each other as humans and as co-parents and friends. I felt like it was Toby's way of saying, "Here's my blessing. Congratulations. I love you no matter what." I thought that was really beautiful and you can tell that there's still so much real love between them. Once you love somebody — you truly love them — you could never stop loving them. It might just be in a different way. But I know! I thought the same thing. I was like, "Oh my god."

I was like, "If I was Kate's bridesmaid, I would throw her phone across the room right now."

[Laughs] I know, because you don't know what the hell he's calling about! But then, of course, the scene is beautiful. It's necessary for both of them. Not that she needed to be right, but she wanted him to also know that he would be happy, too.

We do see them together at Jack's concert. Is that a sign they've overcome things enough to be friends?

For sure. And we'll see in the future that he is sort of a sounding board for her and always going to be. She's always going to value his opinion. He's the husband that she had and went through all of this with, and of course, the father to her children. Who else understands the Pearsons aside from the Pearsons? Toby and Beth, you know. They will always be close and they will always be friends.

Well, that concert is also presumably after Rebecca's death, so we can finally rule out the possibility of Kate being dead. Are you so relieved that you no longer have to come up with creative ways to answer that question?

Yes, she is at least there at that time period.

Chris Sullivan was saying it was weird filming that, where you both had different partners. Was it the same for you?

Honey, let me tell you something. When I walked on the set, I was like, "Who are you?" She's like, "I know, I'm the new girl." I'm like, "Listen, I know that Kate's moved on, but I don't care." We joke about it because obviously you have to laugh instead of cry, but it is very surreal. It's like, "Huh, why is he touching this other person? Who is this?" It does take some getting used to and also that's the first time I'd worked with with her and in that prosthetic makeup, so all of it was very surreal.

On Kate's first date with Phillip, she is so honest about not being the type of woman that she's seen Phillip with. In that moment, how much of that is her trying to genuinely protect herself and how much is a little bit of self sabotage?

I thought of it as her drawing her boundaries. Because love isn't enough. I'm going to start this out on the right foot. Any time we start a new relationship there's a bit of insecurity, like, "Hey, I'm just going to let you know what you're working with." Some of it is like, "Hey, we were friends. You helped me through this really difficult time. Now we have a romantic interest in each other. But I want to let you know what you're getting into." Because I think any woman, if they're divorced, or they're single parents or whatever they're going through, a lot of people will relate to that particular scene because you feel picked over, like, you're not the shiny, bright, new penny, and you're like, "Are you going to love me still? I'm going to put it all on the table. And you let me know because if not, I'm peace-ing out right now. Because I don't want to get my heart broken." It's her drawing her boundary and saying, "I need to know what you want from me." She felt a bit bulldozed [in the past] in the way that she didn't feel secure enough.

Also, we want to push people away because we want to know if they're going to stay. Am I worth it to you to stay and to deal with the things that are not perfect within me and my life and what it's going to look like? We need people to prove themselves to us. It's all of those things in combination. But I'm sure there's some self-sabotage as well, because it's really hard being hurt and to be vulnerable. We're all broken, but we all think someone's less broken than we are. But it's not true. Like, all those beautiful, broken parts make us who we are. And we just want somebody to love us through all of those. And with all of those.

Next week we finally get to see this wedding, and we have seen many weddings on this show, including one of Kate's. So, how does it compare?

It's so beautiful in the way that it's shot, and there's a lot of fun, but there's a lot of stuff going on within the episode. A lot to do with what Kevin's [Justin Hartley] going through. There's this calm about Kate and about Phillip and the whole ceremony that I feel like it's come through the maturity of who they are as people. Then there's the decline of Rebecca [Mandy Moore], which is really difficult, but the way she shows up for Kate, it's very touching.

Sophie [Alexandra Breckenridge] was at this engagement party. So can we assume she's now close enough friends with Kate to be at the wedding as well?

Yeah, definitely. I mean, they've been trying to rekindle their friendship and yes, she will be there. It's just we don't know who she is going to be there with.

Would you say that this wedding is maybe a little breath of fun before we get really dramatic again in this final stretch of episodes?

Yes! There are some really great moments on the dance floor and there's lightness throughout that. But you're absolutely right. Some light before the really hard stuff starts.

This interview has been edited and condensed for length and clarity.

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