We cross the Queensboro Bridge in what feels like record time, moving against the heavy flow of commuters, racing toward the lights of Manhattan. Something about our speed, and my driver's haphazard lane changes, makes my departure from Leo's apartment feel like a very narrow escape. One swerve away from disaster.

As I sit in the middle of the backseat and stare through the partition out the front window, I struggle to digest the last twenty-four hours, and especially the past few minutes, feeling my first pang of remorse for crossing that black-and-white, physical line.

I can't believe I cheated on my husband—on Andy.

With a measure of self-serving irony, I reassure myself that perhaps I needed to kiss Leo to really let go of him—and dismiss the notion that staying in my marriage is any version of settling, or that I'm with Andy by default. After all, isn't settling about having no options at all? About taking something because it's better than nothing? I finally had a real choice. And I chose.

This epiphany is followed by another flash of insight, as I realize that for the longest time, I saw Andy as perfect, and our life together as perfect. And in some bizarre way, once Leo came back into my life, this yellow-brick road started to feel like settling. Settling for perfection, for all the things that you're supposed to want. A good family. A beautiful home. Wealth. It was almost as if I discounted my feelings, because surely I couldn't truly be in love with Andy, too, on top of all those check marks in his column. Subconsciously, I think I assumed that any feelings I had for dark, difficult, distant Leo had to be more legitimate. The stuff of sad love songs.

As we navigate our way through Upper East Side traffic, I remember how my mother once told me that it's just as easy to love a rich man as a poor one, one of her many bits of advice that seemed old-fashioned and inapplicable to me—and not only because I was still a kid. We were in the parking lot of the bank, and had just run into her high school boyfriend, a guy named Mike Callas who my mother had broken up with for my father after Mike left for college. Suzanne and I had looked at his yearbook photo plenty of times, deciding that despite dopey-looking ears, he was pretty cute with loads of dark, wavy hair. But upon our meeting, the hair was mostly gone, making his ears look even bigger, and he had faded into just another doughy, middle-aged man with nondescript features. Making matters worse, he had a smile too big to trust—although maybe I just assumed the last part because he drove off in a flashy Cadillac right after kissing my mother's hand and making her giggle. Still, I sensed no real nostalgia or misgivings from my mother—even after her rather unromantic advice—although perhaps I simply wasn't old enough to look for it.

But now I wonder what she was really thinking at the time, how she truly felt about my father and Mike. Did she ever regret her choices? Were her decisions more clear-cut than mine—or are there always shades of gray when it comes to matters of the heart? I wish I could ask her, but suddenly feel her answer, just as I picture Andy in our kitchen with his loosened tie, disheveled suit. I envision him carefully reading the instructions on a box of frozen pizza, contemplating whether to microwave it or go the extra mile and preheat the oven, all the while doing his best to forget me and his note on the counter.

If you go, don't come back.

I realize with a stab of fear that just because I am making my choice, doesn't mean that Andy will make the same one. Especially if I tell him what I just did with Leo—which I see no real way around. Panic rises in me as I feel Andy slipping away from me. I suddenly want to see his face more than anything in the world—something that impending loss has a way of doing to you.

"Change of plans," I say, leaning toward the front seat.

"Where to now?" my driver says.

My heart pounds as I blurt out the address of my old apartment. Our old apartment. I need to be there again. I need to remember how it was. How it can still be again, with a lot of work and a little luck.

My cabbie nods nonchalantly, turning down Second Avenue. Signs, lights, cabs, people blur by my window. I close my eyes. When I open them again, we are turning onto Thirty-seventh Street. I take a deep breath and slowly exhale, feeling both relieved and remorseful as I pay my fare, step out of the cab, and gather my bags.

Alone on the sidewalk, I gaze up at our building and the black night enveloping it. Then I sit on the worn stone steps and find my phone in my pocket. Before I can change my mind, I dial Andy's cell, shocked when his hello comes back live.

"Hi," I say, thinking that it feels like days—years—since we last talked.

I wait for him to speak, but when he doesn't, I say, "Guess where I am?"

"Where?" he says, sounding remote, weary, and very wary. He is clearly in no mood for a guessing game. I can't blame him for that. I can't blame him for much.

"Our old apartment," I say, shivering.

He doesn't ask why. Perhaps because he knows why. I know, too—even though I'm having trouble pinpointing it.

"Lights are on at our place," I say, looking up at our living room windows and imagining the cozy, warm scene inside. It occurs to me that the new residents could be miserable, but somehow I doubt it.

"Oh, yeah?" Andy says distractedly.

"Yeah," I say as I hear someone talking in the background. Maybe it's the television. Or maybe he's out, at a bar or restaurant, contemplating the singles scene. My mind races as I consider what to say next, but everything feels fragile and fraught with landmines, lies of omission, half-truths.

"Do you hate me?" I finally say, realizing that I had a similar exchange with Leo earlier, when he accused me of hating him when we broke up. I wonder why hate so often feels like a component of love—or at least a measuring stick for it. I hold my breath, awaiting his response.

He finally sighs and says, "Ellen. You know I don't hate you."

Not yet, I think, fearing that I'll never summon the courage to tell him what I did, but praying that I will someday have the opportunity to cross that bridge.

"I'm so sorry, Andy," I say, apologizing for more than he yet knows.

He hesitates, as I wonder if he somehow, instinctively, knows what I did—and maybe even why I did it. There is a catch in his voice as he says, "I'm sorry, too."

Instead of feeling relief or gratitude, more guilt washes over me. Andy's certainly not faultless—no one ever is in a marriage—but in comparison to what I've just done, he has nothing to be sorry for. Not our move to Atlanta. Not siding with Ginny. Not all the golf. Not the disregard he seems to have for my career. Not even his threat last night—which suddenly seems entirely fair.

A bloated few seconds pass before he says, "So I just got off the phone with Webb."

Something tells me that he is not making small talk. "Is Margot okay?" I ask.

"Yeah," Andy says. "But based on her intermittent groans, I'd say there's a baby on the way."

My heart skips a beat and my throat tightens. "She's in labor?"

"I think so," Andy says. "False alarm this afternoon. She went to the hospital, and they sent her home. But they're on their way back in now. Her contractions are about eight minutes apart..."

I look at my watch and cross my fingers that the baby comes tomorrow. Not on the day that I kissed Leo. It is a technicality, but at this point, I will take what I can get.

"So exciting," I say. And I am excited—but wistful and sad, too, remembering how I once pictured this moment.

I suddenly realize that sometime over the last few hours, I have absolved Margot for what she did—and hope she will someday forgive me, too. I think of how life takes unexpected twists and turns, sometimes through sheer happenstance—like running into Leo on the street. Sometimes through calculated decisions—like Margot's. Or mine, tonight, when I left Leo. In the end, it can all be called fate, but to me, it is more a matter of faith.

"Are you going to the hospital?" I ask Andy.

"Not yet..." he says, his voice trailing off.

"I wish I were with you," I say, realizing with relief and gratitude and absolute joy that it is the truth. I wish I were with my whole family.

"In Atlanta or New York?" he asks somewhat wryly—enough for me to know that if he's not smiling, he very nearly is.

"Doesn't matter," I say as a cab turns onto our old block and slows in front of me. I look up at the sky, wishing I could see stars—or at least the moon—before returning my gaze to the taxi. Then, the door swings open, and Andy appears before me, wearing the exact suit and red tie I just imagined, along with his navy overcoat. For a few seconds, I am confused in that thrilling way I haven't felt since I was a child, back when I still believed in magic—and other things too good to be true. Then I see Andy's hesitant, hopeful smile—one that I will never forget—and I know that this is really happening. It is good and true.

"Hey, there," he says, taking the few steps toward me.

"Hey, there," I say, standing, returning his smile. "What are you doing... here?"

"Finding you," he says, looking up at me. He puts his hand on the railing, inches from mine.

"How...?" I say, searching for the right question.

"I flew up this evening... I was already in a cab when you called..."

My mind clicks through the logistics as it sinks in that Andy got on a plane to see me, knowing that he could miss the birth of his sister's baby. Tears form again, but this time for very different reasons.

"I can't believe you're here," I say.

"I can't believe I found you here."

"I'm sorry," I say again, now crying.

"Oh, honey. Don't," he says tenderly. "I shouldn't have changed our life and expected you to roll with everything... It wasn't fair."

He takes one step up, so now we are a stair apart, looking into each other's eyes, but not yet touching. "I want you to be happy," he whispers.

"I know," I say, thinking of my work, New York, all the things I miss about our old life. "But I shouldn't have left. Not like that."

"Maybe you had to."

"Maybe," I say, thinking of my final embrace with Leo, that last kiss. How different this moment feels, for so many reasons. I tell myself that no two loves are identical—but that I don't have to compare anymore. "I'm still sorry..."

"It doesn't matter now," Andy says—and although I'm not sure exactly what he means, I also know entirely what he means.

"Tell me we're going to be okay," I say, wiping away my tears as more stream down my cheeks.

"We're going to be better than okay," he says, his eyes welling, too.

I collapse into him, remembering that night washing dishes in his parents' kitchen when I first wondered if I could actually fall in love with Margot's brother. I remember deciding that it was possible—that anything is possible—and then, sure enough, it happened. And right now, under the dark autumn sky, I remember exactly why it happened—if there ever really is a why when it comes to love.

"Let's go home," I breathe into Andy's ear, hopeful that we can still get a flight back to Atlanta tonight.

"Are you sure?" he says, his voice low, familiar, sexy.

"Yes, I'm sure," I say, thinking that for the first time since I saw Leo in the intersection, maybe the first time ever, I am following my head and my heart. Both have led me here, to this decision, to this moment, to Andy. It is exactly where I belong and where I want to stay, forever.