Welcome to It’s Complicated, stories on the sometimes frustrating, sometimes confusing, always engrossing subject of modern relationships. (Send submissions to itscomplicated@nymag.com.) Photo: Remus Kotsell/Getty Images

I twist the band on my left ring finger. I never know what to do with my hands, especially when I’m nervous.

I’m at McDonald’s. I see him at the door before he sees me. I watch him look around the room. My heart is beating so fast it’s making me dizzy. The whole scene freezes.

I am transported back 20 years: surrounded by Gothic architecture on our East Coast college campus. Our backpack straps around both shoulders on a crisp day, our hands in each other’s jacket pockets as we met up briefly between classes — a kiss, a hug, a quick story. We were a brochure for young love. We made it look good; we made it look easy. And it was good and easy, for a very long time.

Now, I see him see me and his face lights up. I know that face by heart. I look away, pretend to dig through my purse. I can feel any and all sense and rationality leaving my body.

How many times have I imagined this meeting in the past decade? How many versions have played through my mind — the angry, the passionate, the blasé version — now that we’ve both moved on, married other people, and had kids?

I rise to hug him. Our bodies still fit so well together. I pull away fast.

We sit, surrounded by glossy tables in the overlit McDonald’s. The restaurant chain holds great significance for us. For our first Valentine’s Day together in the mid-1990’s, he tried to impress me by booking a swanky restaurant. But when we had arrived, waiting for our table, we sized up the portions: tiny, avant-garde shavings of fish, a lone carrot slice, two pieces of lettuce as either garnish or salad, it was difficult to tell. He had muttered, “bullshit,” at the exact same time I had said, “I’m way hungrier than that.” So we left, took the train to a 24-hour McDonald’s, and shared big macs and milkshakes. After that, we celebrated most of our big milestones at McDonald’s.

My hands are shaking. He notices. “It’s just lunch.”

I nod as I try to dab my glistening forehead with my sleeve. “Did you tell your wife about it, then?”

Where does the history go when the relationship ends?

“Hell no,” he says. “Did you tell your husband?”

“Of course not. It would just worry him.” I chose a McDonald’s five towns away from where I live to avoid running into anyone I know. It is loud and crowded and smells like grease and cleaning supplies. It feels illicit.

I let myself really look at him for the first time. He is almost 40 now and has a few gray hairs to prove it. I wonder what he notices in me — new lines around my mouth and eyes? He reaches across the table for my hands. He smiles, and I see the boy I loved in the man across from me. I shake my head and sit on my hands in hopes they’ll stop shaking.

“Can you believe it’s been 12 years since we last saw each other?” he asks.

“Thirteen,” I say. We were on-again, about to be off-again. He always did the breaking up, three times over eight years.

“So you’re in town for business?” I ask.

He nods, waves his hand in the air as if to do away with any small talk. “I found some of our emails,” he says. “When I was moving a few years ago. Our exchanges back and forth. I saved them all, you know. Some were from our best days in college; some were during the bad ones, long distance. Through all of it —” he clears his throat. “We were really in love.” He says it like it’s a newsflash.

“Yeah,” I say. “Of course. You seem surprised.”

“We were so young.”

I nod.

“And yet, we knew!”

I nod again. I knew.

His eyes start to water.

“Are you crying?” I ask.

“No,” he says, crying. “It’s just really dusty in this … this ketchup is really spicy,” he says, gesturing to the untouched food between us.

We both laugh, which suddenly makes me cry, too.

“Why are you crying?” he asks. “You miss me as much as I miss you?”

I shake my head, “Not at all. I miss my youth!” I am crying because it is always my hope that I have romanticized the past when it comes to him. Every time I see or talk to him, I’m reminded of the pain I felt in losing him, in losing us.

“It was real.”

“It was real,” I say. And then, surprised by my own honesty, I add: “It doesn’t make what I have now any less real or great, but it does still make me sad.” I say it, and it’s true, yet I’m feeling the memories awakening: In a flash, we’re back reading on that park bench in London. We’re kissing in front of Klimt’s The Kiss in Vienna. We’re dodging cockroaches in the tiny basement apartment in New York. Where does the history go when the relationship ends? Is there a storage locker in the unconscious that keeps the memories until you meet up decades later at a McDonald’s in the middle of nowhere?

He rests his forehead on the table for a moment. I can see that he’s still crying.

“Hey, Buddy,” I say. “What’s going on with you?”

He stands up and moves over to my side of the booth, scoots in next to me, so close our arms touch. Our instinct, still there: We always took such care of one another. When we broke up the first time, while I was still in college and he had already graduated and was overseas on a fellowship, we wailed on the phone at international long-distance rates. It was not as much a breakup as a severing, a physical pain. When we hung up that night, he called my best friend and told her to go to my dorm room and stay with me. She did. I loved the way he loved me, even when he was breaking my heart.

I was barely 19 the night we met, at a dorm party. I was punch-drunk and overconfident, lit up with a combination of cheap beer and his electric eyes searing through me. I told him I was going to be a writer someday.

“What will you write?” he had asked, leaning closer toward me. “Mystery novels? Biographies?”

He was so handsome it was offensive. I had to back up to take it all in, his big brown eyes and broad shoulders. I steadied myself on the doorframe. “You know. The kinds of stories with love in the title. I’ll write things that’ll break your heart.”

I didn’t know what heartbreak was. I thought I did, but what I had known up until him were bruises to my ego, nowhere near my heart. Two years later, for my 21st birthday, he gave me an antique Corona typewriter from 1928. The keys were yellowed, rust on the company’s emblem. And inside the paper bail cylinder, a note from him: “For all of your stories with love in the title.”

“I’ve been following your writing career,” he says now.

I laugh. “I’m not even following my writing career,” I say. Lately, I am a professional sandwich-crust-remover and boo-boo kisser. I spend more time in the grocery store than I do at my desk.

“Don’t give up,” he says now. I’ve always felt he was responsible for my becoming a writer: He thought I was extraordinary, and made me believe it, too.

He returns to his side of the booth. The lunchtime crowd has descended on McDonald’s and every table around us is taken. It is noisy, yet all I hear is him. As if picking up where we left off, we are talking, overlapping, and interrupting each other, excitedly, without segues, like we used to every night in our college’s dining hall. But the topics have changed.

“Childbirth, right?” he says, eyes wide, a man who has seen too much.

“Piece of cake,” I deadpan.

We talk about our children, their Lego sets, our favorite books. We’re two old friends making up for lost time.

He leans forward: “Marriage is lonelier than I thought it would be.” He says it just above a whisper across the table. “It’s ‘til death do us part, but even after all these years, I feel her and I growing apart, not closer together.”

I nod emphatically, not saying aloud what I’ve secretly wondered for years: that marriage might be the slowest possible way to kill a once loving relationship. Love and lust are replaced by micromanaging and keeping score over who last loaded the dishwasher. On my worst days, low on sleep and patience with my husband, I have asked myself if I’m with the wrong person, or if this is the nature of marriage, especially while raising very young kids. But these are thoughts I would never tell my ex. They are so fleeting, too damning.

And then he says it, takes a deep breath right before, making me realize that what he’s about to say might be the reason he invited me to lunch: “I have no doubt we would have been ridiculously happy together if we’d gotten married.”

I nod. I know it. “Then why didn’t we?” I blurt out, instantly feeling like I’m cheating on my husband, my family, just by asking it. But I can’t stop: “Why didn’t we end up together? Why did you end it?”

I know the cost to asking these sorts of questions. I’m suddenly as angry as I was 13 years ago, feeling it all again. I’m betrayed by my emotions: If there is still this much anger, there must be a lot of love left, too.

“I thought something better would come along,” he says. His eyes fill with tears, and I don’t have to ask him if something better came along.

It is not how I imagined it, in the version where he admits he messed up. I should feel better. I should feel vindicated. But it feels awful, and I am furious. That we should have been together is worse than if he’d truly found his soul mate in someone else. “Should have” feels so much worse than “could have.”

“I told you,” I say, trying not to raise my voice. I still remember my words from 13 years ago. This doesn’t come along twice in a lifetime. “I begged you at the time to reconsider.”

“I didn’t know then,” he says, his head in his hands.

“Well, why not?” I ask. I know it’s a pointless question. I want to throw something at him. Overturn the table. Scream at the top of my lungs. There are so many things I want to say but can’t. Every thought I’m having feels disrespectful to my children and husband. They are sacred. I look out the window at the PlayPlace. Kids scream, carefree, as they ride a merry-go-round shaped like a hamburger.

My ex abruptly wipes his face. “But now that I have children, I don’t believe in regret. My kids are my life. If things had gone differently, I wouldn’t have them. So. You know, no regrets,” he says, a thousand miles from his wife, weeping into a Big Mac across from me. “But I do wonder what things would have been like.”

I stare at him. My face burns. Before today, the last time I saw him was the final time we broke up. But the last time I spoke to him was two years later, 11 years ago. He called me after he had read in our college’s alumni magazine that I had gotten married. “I just can’t believe you married somebody else,” he said quietly in that phone call. He was already living with the woman who would later become his wife. His restlessness was a perpetual state; he was never happy in the moment. It’s all coming back to me now. He’s an emotional masochist, and for so long, I got hurt by association.

“I have to go,” I say.

“Stay,” he says, and reaches across the table for my hand.

In that moment, I think of my children, the true loves of my life, and my husband, who chose me and continues to every day. I think about the antique typewriter on my desk at home, of the heartbreak I still try to revise.

My hands have stopped shaking now, and I finally know what to do with them: I squeeze his hand, then wave good-bye.