When one of your children cuts the other’s hair, the result usually involves an emergency appointment somewhere expensive, after which the victim will still look unsettlingly Benedictine, but now symmetrical. With immaculate planning (not), I have spaced my offspring out by almost a decade, thus neatly avoiding this pitfall. So I am nonchalantly stacking the dishwasher while Lola positions her sister on the piano stool and makes ready to remove a foot of split ends.

I am a lucky woman. I have two beautiful daughters who love each other and still tolerate me. Lola is 19 and lives at home – possibly the happy side-effect of stonking property prices, plus the fact that I posses a magic washing machine that also automatically dries, folds and neatly puts clothes back into drawers. I prefer, however, to interpret the cohabitation as evidence of genuine fondness.

I am also a prisoner’s wife – a single parent without the upside of singledom. Here were all are: a four-legged stool fighting to balance as three, recalibrating and remoulding ourselves in an attempt to defy the expectation that we will fall.

I used to pride myself on the freedom I gave my children. Now neediness binds us all. The truth is that, without Lola it doesn’t work. We need her. Summa, who is 10, doesn’t get to choose. With her dad in prison, she is stuck with me, and when we reach the inevitable standoffs that happen when everyone is tired and trying not to fall down the hole that he has left in our lives, her dependence on me terrifies her into rage and then – so much more painfully – misery.

One day, I find a scribbled card hidden in a book. On the front, in desperate capitals, is written “SOS”. Inside it reads: “Daddy, I am having a lot of trouble with Mummy. I don’t know what to do when she is mean to me and Lola is not here. I miss you so so so so much. I love you so so so so much.”

I don’t know what to do either, but Lola mostly does, and when she doesn’t, she is at least somewhere else to go: a pocket of oxygen. When my patience is threadbare she can get her sister’s teeth cleaned, hair brushed and happily to bed with quasi-magical rapidity. She forgoes after-work drinks so I can go to parents’ evenings. She papers over the cracks, brings home friends and makes the house live again.

A prison family is always working around holes: the space at the table where he used to sit, the blank on the bank statement under income, the deserted bed. Sometimes there is so much nothing that I think I’ll tumble into it. For families of long-term prisoners, there is too much time to wish away. You can’t sit it out. You have to live and fill the space, but only with things that you can take out again one day when he returns.

We get a lodger and a hamster. Neither is likely to be with us for long, so we should be safe there. Despite its inferior size, the hamster is unquestionably the noisier and more troublesome one of the two. I had worried about sharing my life with a stranger. Now I am praying that Francoise’s boyfriend won’t propose anything catastrophic, such as marriage, and try to steal her back from us.

The hamster was only acquired after dire threats that the creature would die in its own filth before I would clean or feed it – and I make Summa sign a solemn ownership document for good measure. I needn’t have worried. She loves that thing and cares for it like a baby. It seems that the best antidote to loss is love, or at least extra bodies … but where does that leaves me?

Alone and awake is the short answer. For the first six months, I didn’t sleep much in any shape or form. Nights were plagued by desperate fantasies that I had managed to get inside the prison. Even asleep, I never imagined that he had come out: that thought is a prayer I incant too often for it to slip into the unconscious mind where dreams arise.

After a few forays into sleeping pills and the horrid catatonia of the day after, I gave up and let insomnia have its way. Summa soon joined me, her nightmares more violent and vivid than mine, bringing with her the dog, and so my quarters became a busy place of wakeful mind, fitful, sweaty child slumber and snoring terrier.

A year in, the dreams have passed and sleep has returned. It is surprising what you get used to when you stop fighting. They say that in jail you either get zen or die. I am still beset by my nocturnal squatter: unwelcome seasonal insects, bumps in the night and summer’s tardy sundown are all sure to propel Summa sleepily towards my lodgings, wrapped always in her dad’s scarf – the one she believes still smells of him. Lola prefers the tattooed biceps of her current squeeze: understandable and frankly fortuitous from a space perspective.

Waking alone is hardest of all. I infinitely prefer the mornings when two gentle farts inform me that my youngest is present (an alarm call I would have found less endearing from my husband). Invariably there will then follow my daily sudoku as I work out how, before 7am, to respond to conversational gambits such as: “Mummy, can we adopt a baby?” (One-word answers are apparently unacceptable.) But I’ll take tricky and unreasonable over lonely any day of the week.

Is it better to stop missing him and fill in the holes? When someone dies, perhaps in time you can move on. It is not that I wish my husband dead: remembering that he is not is what keeps me going. I know I am lucky. In the scale of adversities, this is all right. It is nothing at all compared with chronic illness or, God forbid, the loss of a child, but his absence is nonetheless like a puncture wound whose edges I don’t know how to heal. If I really stop the bleeding and ease the pain, how will I feel him then?

The haircut is a triumph. The remorse that will come with the realisation that “up do’s” are now history is still roughly three days away, and so the girls disperse cheerily to bed. We have come a long way.

I scoop up handfuls of shiny chestnut hair. It feels wasteful to throw away something so beautiful. How many times did he kiss the top of that head or brush those tangled ends? I dig deep and shove the precious locks into the bin before the macabre hoarding urge overtakes me. You have to let go. You have to drop like Alice down the rabbit hole, and with practice you may even catch 40 winks on the way down.

Lisa Deen is a pseudonym. Other names have been changed