The dilemma I have a good friend I have known since before I could walk. We were at school and college together and share many friends. Our parents and older siblings are friends, too. We also lived together for years, although I moved out recently. This woman is charming, charismatic, very clever and funny. She lights up a room. But over the past few years, I have found her increasingly difficult. She dominates every social situation. But because we’re considered a double act and I am more introverted, I feel like the lesser of two halves. I find myself shrinking. She constantly repeats things I’ve told her in confidence. From when I was young, she’s put down friends I make independently of her. Now I have just found out she wants to apply for a job where I work. I’m very upset. It’s a small company and we’d have to work together closely. I know this would be toxic. When we lived together, I poured a lot of energy into work. That space felt untouchable. Now she’s trying to move in on it and I feel very angry.

Mariella replies Me too! Friends are only friends as long as they act like them. There’s no point maintaining an intimate relationship with somebody who doesn’t have your welfare at the forefront of their priorities. There are plenty of acquaintances and strangers who can rustle up a put-down, break your trust, envy your success or relish your failures. A friend does none of these and the minute they do it’s time to re-evaluate your union.

This woman sounds like she long ago lost her right to intimacy with you, so it begs the question of why you are still humouring her. So much of what you outline involves definite red lines, so it’s odd that continued transgressions create resentment in you rather than propel you into action. It’s possible, of course, that much of what you’ve described is subjective. Your friend may dominate social situations, but is she aware of it or just expressing herself? Does she know she makes you feel like the lesser of two halves or is that an emotional reaction of yours that might seem irrational to others?

Your friend may simply be oblivious to her impact on you

What is apparent is that communication between you is far from what it should be. I’ve no idea whether her behaviour is simply your friend being herself or undertaken to keep you in your place. You offer little investigation of her psychology, which gives me hope, because the advice I’m going to give is that this is a clear example of two people who need to talk. At the stage you are currently there is little to lose, so the fear of losing her shouldn’t dominate your approach.

Carrying friends along for historical reasons is like moving through life with rocks in your pockets, weighing you down, but not offering anything in return. I’m the first person to encourage long friendships as important, rich and valuable but, if your relationship is one in name only, you need to shake up the status quo.

There’s a line that can’t be crossed here and that’s her joining your firm. That she wants to highlights, either her total disregard for your feelings or, less dramatically, her inability to put herself in your shoes. You’re going to need to sit her down and explain that your job is really important to you and that her presence there would be inappropriate and unhelpful. Chances are this conversation may bring to the fore other resentments you’ve outlined to me, but I suspect not to her.

Which brings me to my final point. It’s perfectly possible that your pal is the unwitting instigator of your insecurities, that her vision of your friendship is altogether different and that everything you are saying will come as news. That’s why you need to take a serious look at the emotions she provokes and work out what is her doing and what is the result of your insecurities.

Feeling the Tweedledee to her Tweedledum is something you can change. People don’t make space for us in this world. It’s up to us to squeeze in and make our voices heard. Your friend may lack sensitivity, so simply be oblivious to her impact on you. Much of what goes on between our ears needs to be aired and shared. In this brave new world of texts and emails, there’s little room for nuance – and a lot for misunderstanding. Emojis don’t compensate for the pitch of a friend’s tone and the warmth of their voice. So much is lost that sometimes you can’t blame people for insensitivity. There is a different way to read your letter, which is that your friend is devoted to you and can’t think of anything nicer than touching toes at neighbouring desks at work. It’s hardly a crime, just a misreading of your desires.

Either way you are the one who has to take action by abandoning your supporting role to claim the spotlight for your own feelings. Whether oiled by alcohol or over a coffee, you need to express what you are feeling and gauge the worth of your friendship by how she responds. You may be in for a pleasant surprise in that she’s simply failed to read the signals – or she may be a Machiavellian monster, determined to keep pulling your strings. Either way, in this instance, ignorance is far from bliss and it’s time you two did some talking.

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

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