She shook her head. ‘He didn’t come home last night, unsurprisingly. I doubt he’ll come back. He knows what this means to us.’

I knew, too. It was a betrayal almost too huge to contemplate. In spite of how devastated I felt for Matt and Abbie, I couldn’t help imagining how Andy must be feeling – the vast weight of guilt, shame and regret he’d be burdened with; the fear and desperation that must have driven him to do such a thing.

‘I can help,’ I offered. ‘I got a decent bonus at work this year. I can pay you some of it – maybe not all, but some. It would be a gift, not a loan.’

‘We can’t take your money, Kate. Absolutely not. And anyway, the money – I mean, it’s a big deal. But it’s not the biggest deal.’

I nodded, squeezing her damp, icy hands across the table. No matter how large the sum, it was a pittance compared to the loss of trust, the end of a friendship that had endured for so long. We talked around it for almost two hours, knowing that no resolution could be found, and by the time Matt came home, Abbie was calmer, able to make plans to save harder, forgo holidays, put off having a baby for a few more years until they were financially stable again.

It was evening by the time I left, making my way home through the spring rain, my thoughts in turmoil. What Andy had done was unforgivable – but also not entirely his fault. He would never have chosen to do this. He was in the grip of an addiction that was bigger than friendship, more powerful than loyalty, stronger than Andy himself. It was far, far bigger than I’d allowed myself to admit.

Abbie had made it clear that her friendship with Andy was over, and I didn’t blame her for that. Of course, she hadn’t suggested that I follow suit and cut him out of my life too, but I could see why someone in my position would do just that. On the other hand, though, surely the desperation Andy must have felt, which had led him to steal from his friends, meant that he needed people on his side now more than ever?

By the time I got home, I still hadn’t decided what the right thing to do was – but in the event, the decision was taken out of my hands.

Andy was sitting, huddled, on the steps leading up to my building. He had just one blue IKEA bag with him, containing what I presumed were his worldly goods. He was greasy-haired and unshaven. His clothes looked like they’d been slept in.

‘Come on – let’s get you upstairs.’ I hustled him into the lift. I could smell alcohol on his breath and stale sweat on his body. He was shivering, and as soon as the lift doors closed, he started to cry.

‘I’ve fucked up so badly, Kate,’ he said. ‘I don’t know what to do. I had nowhere else to go.’

‘Yep, you’ve made quite the hash of things,’ I agreed.

‘Have you spoken to Tall Matt and Abs?’

I nodded. ‘I’ve just come from there.’

The lift stopped at my floor, and Andy followed me out into the corridor and then through the front door of my flat, hangdog and humble.

‘Thank you,’ he said. ‘I thought you’d tell me to sling my hook. I wouldn’t have blamed you if you did.’

‘Get in the shower and I’ll order some food. Pizza?’

‘Anything. I haven’t eaten since yesterday morning.’

‘Okay.’

I waited until I could hear the shower running, phoned in the pizza order (extra-large meal deal with a stuffed crust, a tub of Häagen-Dazs and a two-litre bottle of Fanta) and poured myself a glass of water instead of the large white wine I so badly wanted.

I knew I had to act fast and decisively. Now, with Andy fragile and remorseful, he would probably listen to what I had to say; tomorrow, after a meal and a good sleep, his usual bravado would return and with it what had become his usual behaviour. Hunched over my laptop, I embarked on a rapid research session, and by the time Andy emerged from the shower, already looking significantly brighter, I had a plan.

Abbie and Matt had been too kind, too trusting – they’d let themselves be taken for mugs. I wasn’t going to let that happen to me.

‘Thanks for letting me stay, Katie babe,’ Andy said, curling on the sofa with his feet up. ‘You’re an angel in human form.’

‘I’m not letting you stay.’ For the second time that day, I said, ‘I got a decent bonus at work this year. I’m paying for you to go to rehab.’

Andy laughed and sang the line from the Amy Winehouse song, ending with an only slightly half-hearted, ‘No, no, no.’

‘Yes, yes, yes. You know it makes sense, Andy. You can’t go on like this. You’ll lose all your friends. You could end up killing yourself.’

‘I wouldn’t lose you, would I, Katie babe?’ He looked up at me, his blue eyes imploring.

It took every ounce of resolve I had to say, ‘If you did to me what you did to Abs and Matt, you one hundred per cent would. And if you don’t do what I’m asking, it’s one hundred per cent done between us. Game over.’

I saw his face slacken with acceptance, and I realised he really, really believed I meant it.

At the time, I even believed it myself.