The library was unusually busy that Tuesday. Spring fever had hit our small town, and people were emerging from their winter hibernation, eager for new books, new stories, new possibilities. I spent most of the morning helping Mrs. Chen find recipes for her granddaughter’s wedding reception and assisting a group of college students with research for their senior projects.

It was during my lunch break that I first noticed something was wrong.

I was sitting in the staff room, eating a turkey sandwich and scrolling through my phone, when I saw the first message from an unknown number: “You might want to check your husband’s Instagram.”

My stomach tightened. Marcus barely used social media. He had accounts, sure, but he rarely posted anything beyond the occasional work achievement or anniversary photo. I opened Instagram, found his profile, and scrolled through his recent posts.

Nothing seemed unusual at first. A photo of his morning coffee. A sunset from last weekend’s drive. A picture of us at dinner from a few weeks ago. But then I saw it—a post from earlier that morning that I hadn’t noticed before.

It was a photo of two coffee cups on a restaurant table, steam rising from both. The caption read: “Starting the day right with my inspiration.”

I stared at the image, my sandwich forgotten. We hadn’t had coffee together that morning. I’d been home, he’d been rushing to work. So who had shared that coffee with him?

My phone buzzed again. Another unknown number: “Ask him about the woman at Café Luna.”

My hands were shaking now. I closed Instagram and tried to focus on rational explanations. Maybe it was a work colleague. Maybe the photo was old and he’d just posted it. Maybe someone was playing a cruel joke.

But deep down, a cold certainty was settling in my chest.

I couldn’t concentrate for the rest of the day. Every patron who approached my desk seemed to blur together, every book I shelved felt impossibly heavy. When five o’clock finally arrived, I practically ran to my car.

Marcus’s car wasn’t there yet. I went inside and paced our living room, rehearsing different ways to bring up the mysterious messages, the coffee photo, the growing pit of dread in my stomach. When I heard his key in the lock at quarter past seven, I was sitting on the couch, hands folded, trying to look casual.

“Hey, beautiful,” he said, dropping his briefcase by the door. “Sorry I’m late. Presentation ran long, then Peterson wanted to grab drinks to celebrate.”

“How did it go?” I asked, my voice sounding strange even to my own ears.

“Fantastic. We got the account.” He loosened his tie and headed toward the kitchen. “I’m starving. Should we order that Thai food?”

“Marcus,” I said, not moving from the couch. “We need to talk.”

Something in my tone made him stop. He turned slowly, his expression shifting from casual exhaustion to wariness.

“About what?”

I pulled out my phone and showed him the screenshot I’d taken of his Instagram post. “About this.”

He looked at the image, and I watched his face carefully. There was a flicker of something—guilt? fear?—before his expression smoothed into confusion.

“What about it? It’s just coffee.”

“Where was I when you took this photo?”

“What do you mean? I probably took it this morning before work.”

“Marcus, we didn’t have coffee together this morning. You left the house at seven-thirty. I was still in my pajamas.”