They had come to the wrought-iron gate into the Tower garden. Ramsay lifted the latch and pulled it open to allow her to walk through. But she stood facing him, wanting him to understand.

“I was young,” she said. “I was flattered. I liked him. I didn’t think it would do any harm. When I agreed to get engaged, I never really thought it would end up in marriage. It was an excuse for a party, for being the centre of attention for a while. You know what young girls are like. It made me special.”

Ramsay thought that he did not know at all what young girls were like and shut the gate behind her. He was not wearing gloves and the cold metal of the catch stung his hands as he struggled to fasten it.

“You changed your mind,” he said.

“Yes,” she said. “I changed my mind. Charlie became so serious and intense. He wanted me to spend all my time with him. He was only taking one A-level and some re-sits, but I was doing three A-levels. I wanted to go into nursing. He seemed to think that wasn’t important. Not compared with spending time with him.”

“How long did the engagement last?” he asked.

“Three months,” she said. “Then one evening we had a furious argument and I broke it off. He left school and went to join the army.” She paused. “I was quite proud of that,” she said bitterly. “It seemed very romantic.”

They reached the car. Ramsay opened the passenger door for her, then got in and started the engine so that he could switch on the heater. All of the windows were covered in ice.

“What did you do?” he asked.

“I passed my exams and started training to be a nurse,” she said. “I saw Charlie sometimes when he was home on leave. He was always polite but very distant. I thought he’d made his gesture and the whole thing was over. I met David at a young farmers’ dance and started going out with him, I got pregnant and we got married.” She shrugged. “ That time I thought I’d better see the thing through. On the day before the wedding I had a letter from Charlie saying I was making a terrible mistake and I’d never be happy.”

“And were you?”

“Oh,” she said. “ For a while.”

“When did you leave your husband?”