Dream isn’t quite the right word. I was not asleep when they came – later in the night they turned into dreams, but they began as paralysing episodes of fear. I would lie in bed, convinced beyond all argument that death was imminent, that I was riddled with cancer or another (torturing, humiliating) terminal disease and I had already left it just too late for the doctors to do anything about it. Given that my insides were boiling and every sinew was aching from withdrawal, this was one of the more believable treats served up by the gruesome cinema of my imagination. I believed that Elise was the one dying, not me, and we had missed our chance to save her by focusing on me. I placed myself in the brutalised aftermath of economic or ecological collapse, fleeing marauders in a wasteland of burned-out cars hissing with corpse-fed nature. I killed off my family individually or in batches, by bacillus and calamity, and I prodded my reaction for its deficiencies, for evidence that I was less than functionally human and undeserving of aid. Nightly, I built hell for myself.

Very worst of all – in the sense of being least explicable and most persistent – were the fantasies of accusation, trial and imprisonment. I would be accused of a crime – naturally, a heinous crime – that I had not committed, or that I had somehow committed without meaning to, and I would hurtle through the machinery of justice on skids of official outrage, landing in prison without prospect of release, abandoned by all who had previously cared for me. Not just any prison: a Piranesi nightmare wrapped in suicide nets and jaundiced paint, the one-handed creation of an authoritarian mind, only in my mind, all for me.

That was cold turkey. It was a prison without escape. It was a living death. And when I think about stopping, it’s those waking dreams of prison that come back to me.

I should have made the connection with the conversation that we never had, with the words I never wanted to hear. There I was, every night, imagining an accusation, a charge, and a life sentence, fearing that above all else and not knowing why. And meanwhile, during the day, fearing the words that would traduce me. Addict and alcoholic – I would have no defence. That’s when the talk of moderation and finding a balance would end, and there are no more loopholes or cheats, and you have to stop. For ever.