I sat in the driveway for a long time. The house was silent. The only sound was the hum of the cooling fan under the hood. I felt like I was losing my mind, but I was also perfectly clear.

I have always been a practical woman. My mother taught me that if you want to know the truth, you don’t ask the person who is lying to you. You look at the evidence. I grabbed my camera from the backseat and started taking pictures of the screen. I photographed every single date. I captured the arrival times. I got the departure times.

I went inside and turned on the office printer. The ink smelled like ozone and cold plastic. I printed every page. I watched the paper slide out, one by one. Each one felt like a stone dropping into my stomach. When I was done, I had a stack of paper nearly an inch thick. I sat at the kitchen table and looked up the address on my laptop. It didn’t take long to find out who lived there. Her name is Diana Holt. I had never heard the name before, but when I searched her history, I found her on a company directory for Robert’s firm. She was an assistant in his department. I remembered him mentioning a project back in January. “It’s a big push,” he said. “The new assistant is really helping me out.” I remember saying, “That’s good, dear.” I feel like such a fool.

I didn’t sleep at all. I walked through the house, touching things. I touched the photo of us from our tenth anniversary. I looked at the quilt on the couch that we bought together in Wisconsin. It all felt like a movie set.

It felt like I was playing a character in a life that didn’t exist. I kept thinking about how he would walk through the door at nine-thirty. I kept thinking about what he would say. “How was the study, dear?” “Did you learn anything good?”

He came home at nine-thirty. I was sitting in the dark in the living room. I didn’t turn on a lamp. I wanted to see him walk in. I wanted to see if his face looked the same. He walked in, humming a little tune. He looked tired, but he had a little smile on his lips. “Hey there,” he said. “Why are you sitting in the dark?” I stood up. My legs felt like lead. “I had to check the car,” I said. His smile didn’t falter. “Is something wrong with the car?” he asked. “I don’t know,” I said. “You tell me.”