I knew it must have taken all her courage to ask for my opinion and so her feelings for Lee must be serious. In normal circumstances, Mel would have preferred to disappear off the face of the earth, leaving no trace, than instigate something that might be contentious.

Don’t do it. Avoid him. He’s not normal. He’ll destroy you. These were the first things that flashed through my mind, but I didn’t say any of them. I decided I was being unnecessarily melodramatic, and I loved and love my brother, in spite of everything. I didn’t want to tell Mel the horror story I could have told her; it wouldn’t have been fair to Lee if I had. We all make mistakes, I thought. We all deserve a second chance. Lee was a child when all the bad stuff happened; he couldn’t be blamed, could he?

I realized Mel was waiting for my response. I could feel her growing anxiety pulsing out of my phone. “It’s not really up to me, is it?” I said diplomatically. “I mean, if you and Lee want to start seeing each other, it’s none of my business. I’d be unreasonable if I tried to stop you.”

“Yes, but I still want to know how you’d feel about it,” Mel said. “I’d hate to do anything that’d upset you, or change things between us.”

“I wouldn’t feel great about it,” I admitted. “You’re my best friend. He’s my brother. If you and he get together and stay together, suddenly the loyalties start to shift. You know stuff about me that I don’t want him ever to find out.”

“Nicki, I would never tell Lee anything you’ve told me in confidence,” Mel said solemnly.

I felt better when I heard those words. I thought, Good. I’m covered. Little did I know that, six months later, Mel would summon me for an important chat and explain that, from now on, I wasn’t allowed to tell her anything that she couldn’t share with Lee. She would continue to keep any secrets of mine that had gotten in before the deadline, but this was the cutoff point: I was forbidden from confiding in her in future, unless it was something I didn’t mind Lee knowing about too.

“The thing is, we kind of . . . are already seeing each other,” she went on hurriedly, keen to get it over with now that she’d finally taken the plunge. “Lee’s asked me to move in with him and . . . I’ve said yes.”

“Oh. Well . . . congratulations.”

“Are you sure you don’t mind?” Mel asked.