They celebrate their anniversary. They indulge each other’s outrageous ideas — like sneaking into a Lil Wayne concert by way of an air-conditioning vent — and are always there when their partner in crime needs a physical or psychic lift. When one has a big question to pop to the other, she gets down on one knee.

This isn’t your favorite TV couple.

It’s Abbi and Ilana from “Broad City,” two best friends played by Abbi Jacobson and Ilana Glazer who are generally obsessed with each other. (And yeah, one is a little more obsessed than the other.) They’ve been mistaken for romantic partners. But the genius of “Broad City” is that it elevates friendship above romance. Ilana has an on-and-off boyfriend, but her relationship with Abbi has always been the deeper connection.

That ends in the series’ final episode, which aired Thursday night. In an earlier episode, Abbi stresses about how to tell Ilana that she is moving to Boulder, Colo., for an artist’s residency. When she finally does spit it out, Glazer’s character responds, in true Ilana fashion, by smashing a bunch of candy jars and proclaiming that they need to get Abbi into therapy immediately because “this is an emergency.”

It isn’t an emergency. But a best friend moving away or moving on — to marriage, motherhood or just a best friendship with someone else — can certainly be traumatic. As “Broad City” ends, Ilana is 27 and Abbi is 30. Attached-at-the-hip friendship that springs from shared experiences or similar circumstances in your 20s changes when one or both people’s lives change. And that often happens right around where Ilana and Abbi are now.

Watching Ilana react to Abbi’s news, I remembered something another TV comedian said about the pain that follows when a friendship ends or fades. In her 2015 essay collection “Why Not Me?,” Mindy Kaling describes the sting of losing a close friend. “It hurt way more than most breakups I’d had,” Kaling writes, adding that “there are not many relationships more powerful than that of two women who fall fast and deep into a friendship. It was heartbreaking to be loved and left.”

Big goodbyes might be easier to accept as you age, but the pain is still there. When Cristina Yang (Sandra Oh) left Seattle in the 10th season of “Grey’s Anatomy,” she technically left for a job opportunity in Switzerland — but it was also a kind of breakup for her and Meredith Grey (Ellen Pompeo). They still talk, of course. But they’re not in the thick of each other’s everyday lives, muddling through and dancing it out. Which is, of course, how they say goodbye — with that hip-swinging best-friend ritual and with Cristina telling Meredith, “You’re my person.”

Sometimes a goodbye is more subtle than a physical move. It can simply be one person entering a new stage of life without the other. At the end of Season 5 of Netflix’s “Grace and Frankie,” for example, Grace (Jane Fonda) tells Frankie (Lily Tomlin) that she married her boyfriend Nick (Peter Gallagher). The season ends without resolving whether the two oddball best friends will continue to live together. Nick seems like the kind of guy who would be game to live with Frankie, too. And it’s clear that Grace and Frankie are each other’s partners in a way that’s different from and deeper than what Grace has with Nick. But in Grace remarrying, the shared circumstances that brought the women together — their husbands leaving them for each other — have shifted. Frankie is so floored that she drops to the ground and stares into the sea.

That moment brought me to tears, and I had to text another friend who watches and loves that show. A friend I’ve made through our shared experience of being single and child-free in our 30s. I was realizing that being close to someone and then seeing that ebb and flow isn’t unique to early adulthood. It happens back and forth throughout a lifetime. It’ll happen to us, too.

So yeah, Abbi moving away isn’t an emergency. It’s a natural ending. And though Ilana’s reaction is characteristically over the top, her sadness is real.

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