It has struck me of late how the requirements of being a partner and those of being a parent are often diametrically opposed.

It’s the quintessential conflict at the heart of Jane Austen – do we pick a partner based on practical considerations, like Charlotte Lucas in Pride & Prejudice, or do we marry for love, like Elizabeth Bennet? Actually, since Elizabeth Bennet only really warms up to Mr Darcy after she sees the size of his package (i.e. Pemberley), perhaps Marianne Dashwood from Sense & Sensibility is a better example. Except she decides not to marry the man she loves because she concludes he wouldn’t make her happy, so marries a rich guy old enough to be her father and learns to love him. And while Fanny Price marries for love in Mansfield Park, Edmund is her first cousin. In fact, the only character in Austen free to marry for love is the titular Emma – she’s the only one with an independent fortune who doesn’t need supporting by a man.

But whatever the case, that this is such a preoccupation in Austen’s novels shows that in Georgian times, it was a very real conflict. And so it still is in some areas of the modern world – the upper crust, for example, who seem to marry the person who fits the job description of ‘wife and mother’ while refusing to give up the mistresses they really love (no names mentioned). But for the most part, these days we in the Western world marry for love.

As partners, me and Lizzie are great for each other. While I’m a sensible, reclusive stick-in-the-mud, Lizzie is a childlike, emotionally-liberated basket case. While I fret about rules, money, going out, she ignores all propriety, splashes out on frivolities, and is so restless it’s nigh impossible to pin her down. Throughout our relationship, therefore, she’s encouraged me to let my hair down while I’ve helped her face up to her responsibilities – at least in part. She reminds me that the world is a magical place where fun should be had – I remind her that there are boundaries and we need to stay safe. That’s why we love each other.

Trouble is, the very things that you love in a partner are not necessarily very attractive in the parent of your child. In fact, they’re often the opposite.

Before Izzie was born, we pulled each other towards the middle, but since the birth we seem to have returned to our outer limits – I am the responsible worrier again, Lizzie the frivolous spendthrift.

Unfortunately, these two mutually exclusive positions have been playing havoc in our household of late. The most commonly used phrase in the past six months, since I became primary carer extraordinaire and Lizzie has struggled with her role as mother, has been, ‘Look, you don’t need to make things easier for me, just don’t make them any harder than they already are.’

I hate being the responsible one, the one who has to rein the other in, the one who has to say no more often than he can say yes. But it is the role I’ve had to take. And being a parent spills over into being a partner: those very things I love about Lizzie – her clumsiness, her messiness, her devil-may-care attitude – have lately been driving me insane.

Perhaps it’s because it’s the festive season. Christmas is different as a parent – at least it was for me. Normally I look forward to it, get excited, wake with boundless joy Christmas morn, suffer agonising anti-climax once the presents are opened, recover enough by lunchtime to be contented, and wobble in a confused daze until New Year where I’m filled with hope over the coming months and regret over where I’d considered I’d be by this stage of my life. And Lizzie, well, she lived through every one of those experiences and emotions, and then some.

I didn’t. I lived from day to day, hour to hour. Bottles, milk, solids, steriliser, muslins, bibs, toys, car seat. Have we got enough nappies? The baby wipes? Where’s her extra vest in case she soils this one? Teething gel? Spare dummy? While Lizzie dressed the baby in Christmas jumpers and Santa hats and woke her up to sing Auld Lang Syne, I fed her and changed her and rocked her back to sleep. While Lizzie drank champagne and ripped open presents, I listened to the baby monitor and kept the noise down. I didn’t mind it – Izzie was my stable anchor in the chaos of the silly season – but it hammered home how different we are, as parents, as partners, and as people.

If we were living in Georgian times, choosing our partners based on practical considerations, then, hand on heart, I doubt that many of us would have chosen the people we’re with now. We’d have chosen people who were different, better, smarter, funnier, kinder. I can’t imagine I’m the only person with a young child who’s looked around at other people and thought – if only I’d picked them, how much easier would my life be now?

But such thoughts are nothing more than fantasies. It’s so easy when you’re stressed, tired, overwhelmed, overfed, and surrounded by twinkling lights, to forget the important truth: we’re not living in Georgian times, and we didn’t choose our partners, at least not consciously – our hearts did. Not based on their parenting abilities, but because we loved them and love them still. Because they appealed to some intangible need or desire deep down within ourselves that only they could fulfil.

Lizzie might annoy the hell out of me as the mother of my child, but there’s nobody else I’d rather share my life with. It’s separating out these two conflicting realities that’s the hard part.