I am a woman in her early 70s who has lived half her adult life alone. I divorced in my 40s when my children were older teenagers. The last time I had an intimate relationship with a man was more than a decade ago. I lead a busy, good-quality life with a large circle of female friends. I tried some years ago to “find a man” online, but I found it a largely negative and tedious process. I had given up believing I would experience what it means to be a woman again; to be touched and caressed.

But suddenly, out of nowhere, an attractive, older married man has come into my life. We both belong to a local group. My equilibrium has been thrown off. Emotionally, the idea of having a secret relationship with a married man is ridiculous. It would mean only he could determine when, where and how often we met; there would seldom be time for us to do anything “normal” – dinner with friends, meeting each other’s families, getting to know our respective young grandchildren. He would not be available for support or companionship, only for sex at a time of his bidding. It is madness.

But perhaps it is time for me to break a lifetime’s behaviour, live for the moment and think less about the consequences. That is where he is coming from: he admits he has been a bad husband, but clearly he is keen to repeat the experience. He talks about growth, intimacy and feeling alive. I find his attention and intellect hugely alluring, but also destabilising. I know it would mean having to get used to the pain and pleasure of sexual intimacy on his terms. Perhaps I can live with that. I am beginning to believe that, unlike him, I have nothing to lose and maybe a lot to gain. Am I deluding myself?

I really pondered over your letter; it gave me some sleepless nights. I can see what this man coming into your life means to you. You mention your age. You are clearly principled. I wonder if there ever comes a stage in life when it is permissible to go against what one believes.

You have not mentioned his wife at all. (I am presuming from what you have said that an affair is all he is offering.) I can see why. Perhaps you have convinced yourself she does not matter because he has talked her out of the picture. Perhaps you think you “deserve” this bit of fun. You do deserve to be loved and to have fun. But, beyond the heady early days, are love and fun what you would get?

You were brave enough to get out of a marriage that did not make you happy, and to make a new life for yourself. He has not been so decisive. He is in a marriage that is not working for him, but is doing nothing about it other than chatting up other women (are you the only one?). In time, this trait might start to become deeply unattractive.

You gave a long, admirable list of what he would not provide for you; in doing so, it seems you listed what you would like in a relationship. Yet which of these boxes does he tick? Actually, very few.

I understand that people fall in love while still married and have affairs. But if a relationship cannot grow – and how can this one? – it will start to feel corrosive. Look at the flip side of the emotions he inspires in you and what do you find? Deception is behind all of them. And his deception will become yours.

He lives locally. What if someone found out? How would your “busy, good-quality life” fare? How would you feel about lying to your friends?

He has told you that he has been a bad husband; what makes you think he will not make an equally rubbish secret boyfriend? When people tell us they are no good, we should listen carefully. Always take heed of what a potential partner tells you about themselves when you first meet them: they are rarely so unguarded again. It is also worth noting why his relationship is in the state it is in: there are rich lessons in the details.

I am sure you will hate this answer: it is so sensible! But sometimes there is glory in the sensible decision. In fact, I think it is you who has the most to lose, not him. At first, I thought you wanted permission to say yes to him, but now I am wondering if you are looking for permission to say no. If your younger self thought she deserved more than this, why should your seventysomething self not be equally discerning?

If you do go ahead with this, be really honest with yourself. But if you want to kill it stone-dead, get to know his wife.

• Send your problem to annalisa.barbieri@mac.com. Annalisa regrets she cannot enter into personal correspondence

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