Our relationship is like a dance – a well-known routine we play out every time our paths cross. We both know the steps better than we know the reflections of our own faces; both know the next move that the other will make and, following that, what is expected of us. Doing the dance is like riding a bicycle – no matter how long we are apart, be it hours, days, months, years, the moment we are together we begin the routine. One-step forward, two steps back, making slow progress towards the inevitable finish when once again we will be separated until our paths cross again. And they will – they always do, no matter how hard he might try to avoid me, no matter how many miles he tries to put between us.

It wasn't my intention to work, once again in the same hospital as him. It was simply a choice – Holby or Ghana, Ric or Kumi, rich or poor – and I chose the life I knew rather than the unknown that lay in Ghana. He was furious – from the expression on his face when he realised that I was there, I knew my presence wasn't welcome but I expected that – it never is. He's angry with me – angry that once again I've turned up on his doorstep to turn his life upside down. So angry that he stops dancing and goes it alone, doing a solo jig all the way to the next flight out to Ghana, ironically taking the job which I gave up in favour of him. I don't mind – he always dances away from me but he always dances right back to me.

And so he does, returning to Holby mere weeks later, a shamed flush in his cheeks and a half-cooked story about wishing to get to know his grandson. I've been expecting this – in our own personal tango this has always been his next step. He comes back, not for me but 'for the children', full of excuses and shame at running away in the first place. There's always residual anger – he would never have had to run if I didn't persist in showing up in his life, time and time again – but also fondness. He tells me that my Grandma doesn't know the first thing about the damage she has done to his sanity, tells me that just sometimes he'd like me to stop being so relentlessly jolly and get miserable, lose my temper, get a vice. He ignores me when I point out that he has enough temper and vices for the both of us put together, that there is nothing wrong with being jolly – being miserable never gets you anywhere in life. This is a conversation that we have had many times – a comforting waltz that we both know by heart.

But something has changed – almost imperceptibly he has shifted from me. He's dancing with someone else. Someone younger. Someone more beautiful. Someone married. He thinks I don't notice him watch her as she strolls through AAU, lost in conversation with another registrar, thinks I don't see the admiration in his eyes. Admiration that he used to have for me. He denies it – tells me that she's his best friend and nothing more – and yet there is something in the way he is around her and around her husband. He resents them being together – he wants her for himself, and I can't bring myself to resent this but it saddens me – our dance is slowing, perhaps ending for the last time.

Still I continue with my steps in the routine – I counsel his daughter, soothe his fevered brow when he gets grief from the powers that be and maintain my constant presence in the background. He's lost his rhythm and he steps on my toes, too busy watching the other woman dancing with her husband to pay any attention to me. We used to be perfect dancing partners – in tune with each other and the music that we danced to – but now we have gone from being the perfect ten to a slightly mediocre five if the judge is feeling generous, but still it continues. We fight, we make up, he gets himself a reputation with the powers that be, I stand up for him. It's always the same.

Then something happens to pull us together – his grandson is ill and suddenly he needs me. He can't turn to her – ill children are too raw a nerve for her to be of any use to him – and the rest of his support network are too wrapped up in each other to care for him. I sit with him while he talks to me about his fears for the baby and his daughter, and then he cries. He often cries in my presence and I'm never sure whether to take that as a compliment or not. The other woman alienates herself by asking the wrong questions at the wrong time, upsetting the worried parents further. Unknowingly she has danced herself out of his arena.

He doesn't know that I can see him, sipping his drink thoughtfully, flicking the corner of his debit card as his craving for the online casino threatens to overcome him. He knows that I won't let that happen. I go and join him on the balcony where he went to smoke a cigarette, knowing how much I hate the smell. It's just us now – we know that the baby will pull through so I've bought him home to take some rest. So far rest has been a little thin on the ground tonight. I wrap my arms around him, holding him tightly against me and I feel him soften into my embrace, just as he always does in the end, and so the dance goes on.