And, to be fair, they’d been happy days, just the two of us hanging out. Sure, to begin with, I’d had to back away when her boyfriend, Alex, came up to visit, but I was her North Star – ‘the fridge to her magnet’, as she used to say – the one thing she’d always come back to with a knock on the door and a smile. She’d slink into my room in her lounge pants and her glasses with neither apology nor explanation, and there we’d be again, just the two of us.

Grace and Abs. Abs and Grace.

It soon became apparent that Grace was popular. And why wouldn’t she be? A keen and brilliant medical student, she had everything going for her – brains, beauty, emotional intelligence by the bucketload. Her dimpled smile won everyone over, from professors and students to grannies on the bus. She was the type of girl who’d dance or sing with buskers in the stuffy tunnels of the Underground before blowing a kiss and giving them her last fiver; she was on first-name terms with all the Big Issue sellers we ever passed; and she shouted ‘thank you’ to bus drivers. She gave off an aura of loveliness in which everyone wanted to bask – yet she chose to attach herself to me.

‘Go out with your friends,’ I’d tell her. ‘I’m fine on my own’ – and that was the stupid thing in all this: I really was. I was happy to be alone, to lie in my filth and revel in my misery, but she’d roll her eyes and punch my arm, and joke that I was stuck with her now. If Alex wasn’t coming up to stay, she’d bound into my room on weekend mornings, tearing open my curtains and say, ‘Come on! Get up! Let’s go on an adventure!’ She’d suggest ice-skating, tap-dancing, going out to dance Zumba, or taking the train down to the Kentish coast to eat ice cream with Flakes down by the sea.

She told me everything – all the details of her life, even her love life, assuming, incorrectly, that I, too, was no virgin, and I’d look at the floor and flush as she told me about this position and that position and how she liked it best. The intimacy was unnerving. Overwhelming. All-consuming. Flattering. We were chalk and cheese but, somehow, it worked.

For a while.

The coffee machine beeped, startling me from my thoughts and I stared at the email, still not believing that Grace had written to me; not believing that she was coming back. It had been four years since she’d left, just before my gallery show – just before I’d met Rohan. By then I’d lived with her for five years, through university and beyond, until she’d disappeared – pouf! – like a pantomime genie, off to Australia with her latest boyfriend.