Our marriage broke down in an amicably weary way a couple of years ago but my wife seems happy to just drift on, leading largely separate lives in the same house.

Our children are pretty much grown and flown – one has moved out properly and the other is at university most of the time – and don’t seem greatly concerned that their parents rarely exchange a word when the family is all together. They have their own friends and their own preoccupations and I think we can allow ourselves a little bit of pride that we got them to the brink of adulthood without too much in the way of trauma and conflict.

It could be that our “civilised” way of carrying on – polite banter, separate bedrooms, courtesy and smiles – has contributed to my wife’s apparent belief that our non-relationship is perfectly normal and sustainable. And I’m sure that neighbours and acquaintances would be surprised to hear that anything is amiss.

But it is. You can stick whatever label on it that you please – Empty Nest Syndrome, Mid-Life Crisis, Drifting Apart –but the fact is that the only thing my wife and I have in common these days is an address.

I imagine that plenty of couples of my parents’ generation would have found this entirely unremarkable, indeed barely worthy of comment, and simply soldiered on in silence till death did them part. But times – and life expectancy – have changed. I’m in my late 50s and might, with a bit of luck, have 25 reasonably active years ahead of me. Why waste them?

I have explained, in agonisingly polite conversations, that I want to bring this all to a head and start a new life but my wife is reluctant to take that step – she clearly likes our house and neighbourhood and can’t face the upheaval. I have jumped through every procedural hoop to try to prove my case, but have had to face intransigence and refusal to face facts at every stage.

Her view is simply that I am going through a phase, over-dramatising; that all marriages go through rough patches, and so on.

She didn’t want to go to relationship counselling, then complied grumpily, then refused to implement any of the counsellor’s suggestions. Now, having sort-of crossed that bridge, she simply refuses to talk to me about how, and when, and under what terms we might go our separate ways. It is as if she is putting her fingers in her ears and going “La, la, la, everything is going to be fine” when it clearly isn’t.

I can see that the nitty-gritty of the process is not going to be much fun – selling the house, haggling over money, dividing up a quarter of a century’s worth of memory-laden possessions –but I see all of this as a rite of passage to a better life. My wife, as far as I can tell, sees it as a lot of unnecessary unpleasantness that will never happen if she ignores the need for it.

I really believe that all of this could be sorted out pretty amicably and simply if she would simply concede that the game is up and agree to part ways. It is not as if she would be left penniless. But I am afraid that it is going to get very legal and very expensive – for both of us – and the crowning irony of it all is that my wife is a solicitor and should know better than most people what might lie ahead.

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