Underneath the desk, there’s a matching oak filing cabinet. As I unlock it with the key from his sock drawer, I let myself consider that he isn’t lying. Resentment bubbles up and I try to push it down. Surely he could resit in the autumn. Even if he had to repeat the year, it’s not that much longer in the scheme of things.

Though I’m meant to be applying for medicine myself in September. It’s my turn.

I pull out the hanging files. Medical: vaccination certificates, blood-group card, a yellowed leaflet from the school nurse about exercises for flat feet. Credit card: a couple of grand of debt I already knew about; at my suggestion, he’s been transferring the balance to lower rate deals. I am surprised he’s still using it to buy food and drink at the hospital, though. We take cash from our joint account each week to pay for everyday stuff. So what is he using the petty cash for?

As I put the statements back, my hand touches a pocket notebook I’ve never seen, hard-backed with a green cover. Inside, two columns: dates on the left, and on the right a list of numbers. Pages and pages, nearly three years’ worth, though with breaks, including a long gap from when we went to India in July, till late October. Is this column amounts of money? And if so, is it going out, or coming in?

The first date is 28 September 2002. The day of my sister’s wedding. The day he came back from work and interrupted me and Joel kissing . . .

I refuse to think about Joel now.

There’s nowhere left to search. I put everything back where I found it, and read his letter again. What aren’t you telling me, Tim?

I stare at my reflection in the wardrobe mirror. I look wrecked.

The wardrobe! I haul his big suitcase out from the densely packed clothes. He uses it to store the last clothes that haven’t been eaten by moths – we had an attack last month that wiped out the hall carpet and our honeymoon fund by the time we’d paid the pest controller.

There’s no paperwork, but his smart suit is in there, the one he wore to my sister’s wedding. It says a lot about how mundane our lives are that he hasn’t had to wear it since. There’s a strong smell of mothballs, along with something else . . .

Weed.

Could that be it – a secret cannabis habit? No, this is the first time I’ve smelled it on his clothes.

As I lift out the suit, the smell gets stronger. Is there a joint in here? I rifle through the pockets of his trousers and jacket. Nothing.