But she was the love of his life. The implication is there, which raises a raft of questions relating to her life after the divorce.

I can’t go there yet. I’m stuck on the basics, trying to imagine the idea of Paul Schuster and my mother together. On one hand, it’s a no-brainer. Paul was often at our house. He liked being in the kitchen with Mom, while Dad wouldn’t be caught dead there. Paul chipped in with domestic things that Dad considered beneath him. My mother and Paul were easier with each other than either of them was with Tom.

On the other hand, seeing my mother and Paul working together in the kitchen is very different from picturing them in bed. Naked? Limbs linked? Passionate enough to produce … me?

I cover my face with a hand. There are too many emotions to sort through. For the sake of survival, I distance myself, as if their affair was between people I didn’t know.

My hand slips away. “Was it one night only?”

He seems vulnerable, upset by my reaction. But what had he expected? Unbridled excitement? Oh, biological dad, I love you so much?

As he lowers himself to the sea wall, his eyes are older, begging me to understand. “I loved your mother. That started early on. But she loved your father. I had no idea why, but she did. Then he had one affair too many.”

“So it was revenge?” I don’t want to think this is how I was conceived. Actually, I’m wondering whether Paul is right at all. Oh, I’m sure he and Mom had an affair. He couldn’t imagine that. But the idea that he was around our family all those years harboring this huge, intimate, marriage-blowing secret—me—is beyond the pale. Besides which, he loved my mother. He’s said that twice now. If she didn’t love him the same way, there might well have been other men Paul refuses to acknowledge.

“Not revenge,” he says. “It was more a cry for help. She felt rejected by Tom, and came to me. She knew how I felt and, at that point in her life, she needed to know she was loved.”

It sounds innocent enough. Still, Paul helping Eleanor meant cheating on his best friend, not to mention that he hasn’t answered my question. I repeat it. “Was it just one time?”

He runs a hand down the back of his head and gazes at a far-off barge. “It went on for a bit.”

“What’s a bit?” my out-of-body person asks.

His eyes find mine. “A few months.”

“And before and after? How do you know she didn’t have others?”

“I told you that earlier. She said it, and I believed her.”

“Why did it stop?”

“With us? Guilt.”