One of my oldest and closest friends seems attracted to my husband. She is not overtly inappropriate, and I feel her behaviour is unaware / unconscious, but she gives him a lot of attention, giggles at most things he says, follows him with her gaze around a room and although I can’t blame her for fancying him – he is amazing – it is starting to affect my friendship with her.

I think I would find it easier if I didn’t suspect she could, if drunk one night, be hugely inappropriate towards him. She has cheated on all her partners and it makes me distrust that she is capable of controlling her instincts. It doesn’t help that she is also very beautiful and openly sensual, and I find it hard to believe any man wouldn’t want to sleep with her. I thought maybe it was my insecurities making me imagine the dynamic (family history has led to a huge fear of abandonment), but when I talked with my husband, he said he had noticed it, too, but that it was totally one-sided.

I trust him and have never seen him be inappropriate with anybody. Even so, I can’t help watching him and looking for signs that he reciprocates. She is a good friend in all other ways and I want to be able to keep the friendship alive and inclusive with my married life (my husband likes her as a person and wants to be friends), but now I feel I’m waiting for her to step out of line so I can confront her.

I am all for a little flirting, and some well-meaning, charming banter (although that word has less pleasant associations these days). But if it makes you feel uncomfortable, whether or not your friend means it, then it is not acceptable. Instinct is a powerful tool that social conditioning often makes us override. (Do read Gavin de Becker on how and why our instincts are so important and how we ignore them at our peril.)

Joanna Coker is a relationship and sexual therapist (cosrt.org.uk) whom I consulted about your letter. The scenario you describe is one she has seen many times. “Your friend,” she says, “sounds like a partner predator; these people like the challenge [of taking someone’s partner from them].”

I wonder how long you have been married as, although you describe your friend as long-standing, there was something new about this situation, of you, her and your husband.

I also wonder if there is an element of jealousy and possessiveness from your friend aimed at you – not your husband. I wonder if you being “the happily married one” caused her to feel unsettled, abandoned even (if so, this is her issue, not yours), and she wanted to have a little bit of what you have and maybe – however subconsciously – wanted to break up your relationship with your husband to have what she had with you before.

Maybe she was always the more successful one with men, going for quantity over quality and now she may not be happy with how things are. You say nothing of her background, but this is very particular and distinct behaviour that may hint at some damage in her past. However, that is not your responsibility, but hers.

“You are talking,” says Coker, “as if you are going to stand by until you have actual evidence. But once she has stepped over the line, you will already be hurt, your relationship will have suffered and, maybe, even if without meaning to, your husband will have stepped over the line, too. It sounds as if you’re leaving it in the lap of the gods. Why?”

It is hard to bring these things up and face up to fears, the reality of which you question, but it is bothering you enough to write in, and your husband acknowledges your friend’s behaviour; so you need to do nothing and hope it settles (or explodes), or act.

Whether you decide to say something, or your husband does, or you both do, is a matter for you to think about. If it were me, I would say something (although it is really important that you and your husband play as a team). If you do, Coker recommends something direct, along the lines of: “I’ve noticed your behaviour towards my husband and I don’t like it. It upsets me and I would like you to change it.”

I would probably not have the guts to say that, so I would go around the problem and temper it with something like: “We’ve been friends for a really long time and I do really like you, but you do something that I don’t like and I’d like to talk to you about it.” Once you have told her, remember, if she continues to do it then she really doesn’t have your best interests at heart.

“If she really is your closest and oldest friend,” says Coker “she should be able to take it.”

What if she doesn’t respond well, or denies it? “If she does this,” advises Coker, “then you will need to make a decision about what you do. I don’t think she can be a good friend and upset you. A good friend doesn’t do that.”

Coker predicts that she will either “stop it or ramp it up” and that in itself will reveal her motivations.

“It is really important to have boundaries in a relationship and it sounds as if one of yours is being crossed,” adds Coker. “We all want to have fun, but it needs to be kept on the right side of appropriate.”

Your problems solved

Contact Annalisa Barbieri, The Guardian, Kings Place, 90 York Way, London N1 9GU, or email annalisa.barbieri@mac.com. Annalisa regrets she cannot enter into personal correspondence.

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