Isn’t it possible to improve the parts of your relationship that need revamping, says Mariella, while taking the time and energy to pursue interests outside the partnership?

The dilemma I have been married for 17 years and we have three beautiful children, aged between 12 and 17. Over the past 10 years our marriage has become more and more unsatisfying. We don’t feel emotionally close any more. It seems we are sticking it out for the kids, so neither of us has to leave. However, our loveless, long-term cohabitation is becoming increasingly difficult to bear.

My husband is a kind and good-hearted man, but I have often felt neglected. We hardly talk about things that matter to us, schedule in quality time or have any kind of sexual relationship. I think I have emotionally prepared myself to count on myself if I want to make things happen. At present I can’t even stand to share the same bed with him as I have been feeling a lot of resentment.

I am aware that my husband has his own struggles (supporting his family abroad), which have caused him a lot of financial pressure, tiredness and lack of enthusiasm. But I also feel that I’m not living life to the fullest.

Mariella replies You’re probably right. Over time our relationships do tend to lose their romantic lustre and battling to retain some semblance of an emotional connection, rather than just existing in tolerable proximity, becomes quite the challenge. You two sound like you’ve reached a bit of an impasse and if you’re not careful, whether it’s what you desire or not, you’ll end up allowing inertia to force you apart.

It’s easy to pontificate about tolerance and investment in a relationship and far harder to put it into practice. During times of difficulty it’s imperative we remember why we got hitched in the first place. Can you remember what you felt 17 years ago and isolate the changes that have occurred that have left you feeling dissatisfied today? I replied to a letter recently from a woman who was desperate to get married but whose partner was less enthusiastic, and it got me thinking about why we hitch ourselves to another human being for life. It’s rarely a rational choice. No one is a guaranteed safe bet as a spouse and so many relationships flounder under the weight of expectation, accruing years, or from one partner giving up hope and seeking solace elsewhere.

So why does it seem so imperative to confirm your determination to last the course in front of friends and family, even signing a contract to that effect? Far from being the perfect way to announce your besottedness to the world, it seems to me more of an attempt to shore up the relationship in anticipation of future discord. You don’t need a reminder of your intentions when you can’t wait to rip each other’s clothes off, but it certainly comes in handy when you’re moving your things into the spare bedroom. I don’t mean the dividing of assets in the event of divorce, which is never less than fractious – I mean in terms of thinking long and hard before we call it quits.

It’s far too easy to blame the person standing next to you when so often it’s ourselves we need to look at

It’s not just what we’ve come to feel about our partner that requires careful examination, but also what we might be deluding ourselves about. We’re frequently far more responsible for the frustrated ambitions and tedium in our lives than the person we sleep next to. Everyone who writes to me about being bored in a marriage (and you’re quite the crowd), tells me their husband or wife is kind-hearted and good, that there’s an absence of mutual interests, they feel a lack of emotional connection and have dwindling or nonexistent sex lives. All of those symptoms are as common as marriage itself, and most of them can be improved on.

I’m not suggesting you sentence yourself to a lifetime of tedium, where your ambitions remain on pause and your happiness levels plummet. The opportunity to go solo is always there, but often it’s only the better future we see and not the lucky reality of a good person by our side, there when we fall and supportive of whatever our personal flights of fancy might be. Isn’t it possible, if you married such a decent man, and have had three children with him, to try to improve the parts of your relationship that need revamping while taking the time and energy to pursue interests outside the partnership, that could bring you the stimulation you crave?

No one wants to be Tweedledum and Tweedledee all their lives. There comes a time where the mature thing to do is to accept that you can’t offer each other everything, but you can work together to make a good life and one that balances outside fulfilment and indoor contentment, with no losers. It’s far too easy to blame the person standing next to you when so often it’s ourselves we need to look at. We have the power to change our own destiny – and swapping partners isn’t always or even often the way to go about it.

I realise that plenty of people will read this with incredulity and wonder if I’ve started writing fiction. But looking around me at the many friends and acquaintances who’ve chosen to swap the old for the new, often, what goes around comes around. Whether you’re on marriage number two or 52, the same old demons will come back to haunt you once the thrill of the new has dissipated into the same old story.

If you have a dilemma, send a brief email to mariella.frostrup@observer.co.uk. Follow her on Twitter @mariellaf1