I'm 28, and I miss sharing a bed with friends at sleepovers. I long to experience that kind of intimacy in adulthood.

• I grieved the fact that my best friend and I no longer share a bed during overnight stays.
• As girls, we'd watch movies and share our aspirations while falling asleep beside each other.
• I worried our intimacy would be different, but during a recent visit I realized we're still close.

I arrived in Maine to visit my best friend and her partner amid a long, dogged storm. Talya and Peter had recently traded their studio apartment in Brooklyn for a storybook cottage on a peninsula in Penobscot Bay, and they had far more space than they'd ever had in New York, making it possible for me to stay overnight with them for the first time.

It was also the first time in our 22 years of best friendship that Talya and I would sleep under the same roof without sleeping in the same bed.

At 28, I'd reached this milestone with several other friends. My friends and I had started to rent bigger apartments, buy comfier couches, and move in with partners. I knew that sleeping in separate beds during overnight stays or weekend visits was perfectly normal. We all wanted more privacy, more personal space, and a respite from the disruption in our routines.

But I still worried that our intimacy would never be quite the same — that we'd never feel quite so apart from the world together.

While others had moved on, I missed this intimacy

The trend seemed impossible to reverse. There was nothing to do about it but grieve, reminisce, or move on. But I couldn't seem to move on, and there was something vaguely embarrassing about grieving: I worried about coming across as needy, dramatic, or overly sentimental.

So I said nothing. I couldn't be sure if I never heard anyone talk about it because they felt the same way or because they felt nothing at all.

On my first night in Maine, wind and rain battered the cottage while Peter caramelized onions and Talya scattered rosemary over a dimpled pillow of homemade focaccia. After midnight, Talya and I ascended the stairs and unboxed the new air mattress in her office. We sat cross-legged and talked over the whir.

How incredible it all felt: My oldest friend was now 30 and living in small-town Maine, being loved by a good man. I was just two years younger, a visiting professor at a fancy university in central New York. Both of us were writers.

We wondered aloud what our younger selves would think. I couldn't decide which felt more like a dream: all we'd endured to arrive here together, or the present we found ourselves in, the futures we'd made possible.

Our sleepovers used to consist of R-rated movies and dreams of the future

We decided we would set early alarms. Talya had once been practically nocturnal, but now she suggested waking up even earlier. Eight a.m.? I nodded and felt myself getting choked up as we kissed each other's cheeks, her embrace as familiar and comforting to me as my mother's.

When we were girls, the real magic of the sleepover would've taken place in this dark stretch before sleep. We'd watch R-rated movies and sand our tongues down with green-apple sour straws. We'd stretch out on the comforter and cry to Rilo Kiley and Sufjan Stevens.

Most memorable of all was the time we spent simply fantasizing together.

We imagined our first slow dances, our first kisses. We rendered in detail how we would lose our virginities. We described moving to New York and renting an apartment with exposed brick. We sketched our futures like paintings in a diptych: distinct but adjacent and entwined.

I longed for the intimacy and mundanity of co-sleeping together

In college, I learned about the "social simulation" hypothesis, which proposed that dreams — the kind we experience in sleep — allow us to practice for real life. Sleepover conversation felt exactly like that. If my best friend and I didn't share a bed anymore, how could we share our aspirations and fantasies with such vividness and intricacy? How could I prepare myself for whatever was coming next; how would I know what to do?

The conversations Talya and I had that night in Maine helped keep the fear at bay. But I missed something ineffable in what used to come after the conversation ebbed and my eyes grew heavy. I missed the intimacy and mundanity of co-sleeping itself: drifting off while Talya scrolled on my computer; waking in the middle of the night to hear her talking urgently in her sleep; being woken from a nightmare by her warm palm on my cheek. I even missed our drool-encrusted chins and the hair matted to our foreheads.

During the day, Talya was usually subtly made up and put together. I missed that mussed, guileless, raw version of my best friend.

Sleeping beside a friend is entirely different from sleeping beside a partner, but the idea that I'll never do it again doesn't feel so different from a romantic breakup. We so rarely know the last time is the last time.

Our easy conversation and the new space between us suggested a greater intimacy

The next day, Talya and I walked a 10-mile loop around the peninsula, talking the whole way. I learned that the power had cut out in the cottage after I fell asleep. She described wondering what I was thinking during the outage — what, if we were still 8 or 12 or 20, I would've told her in the moment. It was a gift to hear her say that as I'd drifted off, under the floorboards and insulation and plaster, she'd been thinking of me, too.

That evening, we curled up on her couch to write while Peter sizzled zucchini in fragrant crescents of garlic in the next room. The more I thought about the weekend, the less I felt I had to mourn. The reassurances I'd once received from her — we are close, you need me, I am OK — could be subsumed by greater comforts: the longevity and adaptability of my friendships and the knowledge that my friends are loved, nourished, safe.

Besides, wasn't this independence exactly what we'd dreamed about all those long nights together? What if the new space between our bedrooms was a reflection of an even greater intimacy, the kind that grows up with you?

Later that night, we embraced in the living room before I climbed the stairs. I smiled when I saw four of Talya's rings in a heap on a step overlooking the kitchen, where she must have tossed them before kneading the focaccia. It was such a gift to see my best friend taking up space in the home she'd made. To let the air out of the mattress in the morning and fold it up small.