“A couple of times a week Greg drove to visit a client. But I pretended to be Greg’s assistant, rang up and said that for tax reasons I needed an exact time for when the meeting had taken place. People were very helpful. I’ve marked all those in blue. Even then I was left with the gap between him leaving the office and arriving at the client. But I found a website. If I type in the postcode of the office and the postcode of his client, it gives an exact driving distance and even an estimated journey time. I’ve marked those in red. Obviously, driving in London traffic during the day, it’s not an exact science, but even so it fits pretty well. It took me a day and a half—and look.”

“What?”

“What do you see?”

“Lots of colors,” said Gwen. “Lots of stickers.”

“No,” I said. “It’s what you don’t see. There’s barely a gap over four weeks when I don’t know where he was and what he was doing.”

“Which means?”

“Look at the chart, Gwen,” I said. “It shows Greg working very hard, traveling, eating, buying stuff, going to the movies with me. But where’s the bit when he’s having an affair? Where’s the space for him even to meet the woman he died with?”

There was a long pause.

“Ellie,” she began, “for God’s sake—”

“No,” I said. “Stop. Listen for a moment. I talked to Mary about this—not about this,” I gestured at the charts, “I mean my feelings about Greg. She wasn’t sympathetic. She was even angry with me, as if it was some insult to her that I wasn’t immediately accepting that my husband had been having an affair and had had a crash with the woman he really loved.”

“No one’s saying that,” said Gwen. She looked at my charts almost with an expression of pity. “I don’t really know what to make of this.” She took my hand. “I’m not an expert but I’ve heard that there are stages of grief and at the beginning it’s anger and denial. It’s completely understandable that you feel anger. I think the point of mourning is to get through that and reach some kind of acceptance.”