The dilemma In the summer I met a wonderful woman online. She is kind, clever, good looking and many other positive things. We clicked from the outset and became lovers after a couple of months. We have a combined age of 127, but we both said the sex was the best we’ve ever enjoyed. She told me she loved me – and it was reciprocated. We live 100 miles apart, but that suited our busy lifestyles.

Everything was wonderful and we seemed to be very much on the same wavelength until November, when I was diagnosed with bladder cancer. The treatment is extensive, but hasn’t yet started. She broke up with me over Christmas. She still professes love for me (though we haven’t been in contact for a few weeks), but says she is too busy with work, family and friends to commit to me, and that I would become too needy of her and her time. I don’t agree that I would, but I can see why she might say that. I have recently retired. I miss her terribly and don’t know how to deal with it.

Mariella replies Poor you. In the sporting world that would be considered a double whammy. I’m sorry about your diagnosis, and the demise of your relationship must have been quite a body blow. Whether you are 18 or 80, shades of masochism in romantic behaviour are an enduring strand. Why else would you be mourning someone who failed to support you when you most needed her?

I’m also saddened by the conclusion to your affair, not least because I love receiving letters that confirm passion doesn’t stop at 40-something. The fact that you and your lady friend met, clicked and had some fun is comfort to anyone wondering if celibacy is the only available option for singletons post-60. It’s certainly the impression the cultural and commercial world likes to present. It does sound like you two had a great time and, despite the distance, enjoyed a rewarding relationship.

It may seem heartless, but I do admire her clarity of vision

There are two sides to your story, though, and one is not rose-tinted. Perhaps we expect too much of maturing adults, assuming that, with all their life experience, they’ll treat others kindly and that their love affairs will be less framed by dysfunction than is commonly the case in youth. It’s what evolution is supposedly all about. Yet here’s this woman seemingly scarpering like the most unreliable Casanova at the first indication that she might be called on to provide elevated investment in the relationship. Nobody wants to see into the future and have it involve a nursing outfit and an invalid to care for, but there are people out there living that experience and gleaning satisfaction and joy from being useful to someone they love.

Your condition is not going to render you incapable of normal life, but it might require a partner with an appetite for the compromise and care a less transient love affair might involve. Like many of us, your ex-girlfriend would struggle to qualify in the latter role. Seemingly, having heard your diagnosis, she totted it up along with the other obstacles to easy coupling – like the distance – and came to the conclusion that it was better to move on. It may seem a bit heartless, but I can’t help admiring her clarity of vision. If the boot was on the other foot, are you sure you would have rushed to her hospital bedside to watch over her, weakened, reduced and unavailable for great sex for the time being?

Our idea of romance is built on the likes of Romeo and Juliet, Antony and Cleopatra – lovers who would rather die than lose their grip on each other. It’s no coincidence that none of them were mature adults. As we grow older we are less likely to be seduced by fanciful ideas of what our foreshortening future might have to offer. The woman you’ve been having such fun with, invalided and not quite as perky, might not be as desirable to you as the version you’ve come to know. It’s a conclusion I fear she came to and saved you further agony by knowing her own mind and moving on. Hers may not be the most charitable of choices, but she was admirably decisive and didn’t prolong the potential torture of withdrawal from your life.

I personally like to leave doors open instead of slamming them shut, which is all too often what can happen at the end of a relationship. In this instance, there’s certainly room for reunion. If she values what you once had together as much as you do, I suspect that when she realises it’s a vacancy for a lover not a carer that you have, she may come knocking again. I appreciate that in your moment of need it would be nice to think your lover cared enough to be a presence you could lean on. That’s why I’m hoping a higher-quality candidate will enter your life when you’re back to fitness and good health.

Meanwhile, rather than preoccupy yourself with someone who deserves less of your attention, I suggest you turn your focus inward. Get yourself strong, mentally and physically, for the recovery that lies ahead and let your recent ex become a happy and sustaining memory until her replacement wanders in.

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

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