[Warning: This story contains spoilers from "Love Songs (In the Key of Gallagher)," the fifth season finale for Showtime's Shameless.]

Showtime's Shameless had all of its characters questioning what they knew about love and relationships during Sunday's season five finale, and true to form, to mixed results.

Fiona (Emmy Rossum) was given a choice by her musician husband Gus (Steve Kazee) about whether or not she wanted to be with him — and she ran right into Sean's (Dermot Mulroney) embrace, only for him to point out he doesn't want to be the guy sleeping with a good guy's wife.

Debbie (Emma Kenney) decided she wanted to get pregnant to instantly become part of her teenage boyfriend's (Luca Oriel) picture perfect family forever — without asking him how he felt about a potential baby.

After being publicly dumped by his college sweetheart, Lip (Jeremy Allen White) realized he was falling in love with his college professor (Sasha Alexander) — after her husband watched them in bed together.

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Ian (Cameron Monaghan) saw what a bad relationship his bipolar mother was in and came home to Mickey (Noel Fisher) only to break up with him after a fundamental disagreement about his need to be medicated. The argument left Mickey in tears. Sammi seemingly returned from the dead and took multiple shots at him, leading to a police pursuit. Ian and Fiona returned inside with apaprently little interest in the outcome.

Then there was Frank (William H. Macy), who for the first time actually showed that he was capable of love after Bianca's suicide, even though the career drunk still didn't seem to realize it.

But do any of the Gallaghers really know what love is? The Hollywood Reporter turned to Shameless executive producer John Wells to break down the finale and find out. "They don't have a lot in their lives in the sense of security, and so their relationships become more and more important. A question comes into play for all of them: 'How does love or caring for each other make up for scarcity?' There's constant difficulty in having relationships in the world in which they live," Wells says. "It's all a part of the theme of something larger: looking for meaning in your life. Who are you, and how do your relationships fit into that?"

It's arguable that Frank's actions with Bianca (Bojana Novakovic) were more loving than those with anyone else we've ever seen him interact with on the show, especially his own children. Have we finally seen Frank start to change for the better?

You hope so, but he's such a narcissist because he's such an addict, and he's so focused on his own stuff. It's hard to say yet if he'll use it as an example to others on how he's opened up, or if he's actually at a point where he can change any of his behaviors. Often it's easier to fall in love with — or be swept up in melodrama — with someone who's leaving because there's no long-term commitment. Bianca was fatally ill, but then he found himself attached, and he had to come to terms with it, and that's what we felt was fascinating. But we also want to make sure his shift isn't something that just disappears from the landscape when we come back.

While Frank's marker of maturity came as a surprise, for other characters, like Fiona, it was more gradual. But she's certainly still struggling at the end of the season to choose between Gus and Sean, even though maybe she needs to just choose herself for a change.

We've watched her grow up a bit, and she's a woman now — she presents herself as a woman — and so we have to start addressing that. If there was something kind of cute about [her behavior] when she was 20 years old, it stops being cute in a 26- or 27-year-old. It starts to move into that area of, "Oh, they have to get their shit together." We all have those friends who we thought were funny or messed up when we were in college or high school, but as time goes on, if they're still involved in that same behavior, you're like, "Oh this has turned into sad!" We care deeply about her as a character, and so we really want to watch her make that transition into maturity, which is a lot of what Dermot has been doing on the show. He's saying to her, "You have a lot of potential; you're sort of a fabulous girl, but you're not a girl anymore." He's pointing out the things she does have real world consequences on the people around her now.

If Sean is such a good influence, is it safe to say he's back for season six?

Yes, we have another year with Dermot on the show.

Does that mean Justin Chatwin's exit was really final this time? He and Joan Cusack both left in ways that feel like there could be more story there.

We never want to say never. We could sit down and suddenly come up with a great idea, but for both of those characters, I think it would be fair to say that we love the actors, and we love the characters, but we sort of felt like we would need to find something completely different to do if we were going to bring them back.

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Along similar lines, how do you feel about Sammi's (Emily Bergl) future? It's left open-ended as to whether or not she's going to be locked up for shooting at Mickey.

We like her, but we also felt like we had started to play it with too many of the same beats. If there's something else we can do that's interesting, we love Emily; she was a big part of my [TNT drama] Southland, too. But we haven't quite figured it out yet. it's complicated because we also really enjoyed writing for [Kellen Michael], who plays Chuckie. He's just flat out funny in everything we threw at him.

Yet you locked him in juvie along with Carl (Ethan Cutkosky)!

That ended up being a great story, but it really started because Ethan was going into high school and wanted to be there in the fall to be able to attend his first full year. So we wrote him out of the end of our season in kind of a humanitarian dispensation so he could leave — he's from Chicago — and go back and spend his first full year of high school. We love that character, and we want to have him around more, so we'll have to address that early in season six.

There were so many ups and downs with Mickey and Ian this season, but with Ian returning home, it seems like they are left in a hopeful place despite having broken things off. Do you see this as one rare Gallagher relationship that can go the distance?

I do, but it's really a decision for Noel to make. He was going to do a movie and wasn't prepared to sign on for another year, so I have to check back in with him in a few months and see. He has a very thriving film career, and we really just hired him for a few episodes when we started, but we keep expanding it, and he always comes back when he's available. So, some of where the characters end up will be dictated by availability, but it [also] may be an interesting time for Ian to discover how important Mickey was in his life. It's that thing that often happens when you're younger: you have a relationship that's really difficult and passionate and messy, and then you go away from it and you discover the rest of the world, and sometimes you come back to that first person anyway.

Then there's Debbie, who followed Fiona's footsteps early on with her caretaking but now seems to be making the intentionally bad decision to be a teen mom in a bid to lock down her boyfriend and have a "normal" family.

It's not about bad decisions; it's about her desperate desire to figure out what is normal. She doesn't have any idea. She's got other adults in her life, like her sister Fiona, trying to tell her what that means — but Fiona doesn't really know what it is, either. It's really easy for Debbie to look at Fiona and say, "Oh yeah? You're the one who's supposed to tell me what happiness looks like and how you're supposed to act as an adult?" What really defines Debbie is some desire to find stability. It's about those horrible conversations we have with teenagers all of the time. But particularly in this circumstance, it's heightened. There's been a lot of teenage posturing on her part, but a child takes teenage posturing and puts it in a completely different place, so that's definitely something we'll want to explore this next year.

Are you willing to confirm she is pregnant? As much is assumed from her reaction, we didn't actually see the test results.

Well, I can only confirm that that's what we were doing at the time, but we haven't sat down to figure out where it would got yet. We weren't trying to just be titillating with it or provocative; we wanted to actually say, "What do you do?" when this theoretical thing just got very real.

Things seem to be getting very real for Lip, too, when he says he's in love with Helene. Is this a moment of true growth for him?

I don't think he's ever really been in love with anybody. I don't think he really knows what that is. He's very protective and guarded, and we've always seen him really be much more in control of these things [aside] from something early on with Karen [Laura Slade Wiggins] as a teenager. Now, as an adult, he's [wondering] "How do I act? What's a commitment? Who am I supposed to be? Who am I attracted to?" All of those identity issues have come up for him [and] he doesn't know how to separate them out; he doesn't have any history that allows him to separate out her belief in him and this new world that he's being introduced to. He can't differentiate between that and her obvious interest in being with a younger man who satisfies her sexually but also admires her in a way that makes her feel better about herself. It's something we'll start to explore this coming season.

Overall, this season the Gallaghers went off in their own individual directions a lot. Is that a trend you see continuing?

Yes, because they're all growing up! Those are the things we all have to adjust to and address all of the time. They do leave; they grow up; they have their own experiences. And they want those experiences and their additional maturity to be recognized by the family. And they aren't always, and that's funny and also dramatic.

What did you think of Shameless' fifth season finale? Sound off in the comments below.