The dilemma Last year I accidentally told an old friend I liked him. He said he had no romantic feelings for me, which of course I accepted. Fast forward to now. I recently wrote to him asking for some help with my PhD idea. We messaged each other over it for about an hour and a half. Nothing wrong with that – but I noticed a few hours later that half the messages we exchanged were deleted by him. The content was flirty. He has a girlfriend but it’s complicated. What I don’t get is why did he delete the messages? It’s not unusual for us to be flirty. What’s going on?

Mariella replies Do you really need me to tell you? I’ve realised after two decades in the job (yes, yes, slow learner I know!) that often people write to me so I can spell out clearly what they already suspect but aren’t ready to accept. You certainly back up my theory, as the first part of your letter pretty succinctly sums up what’s causing the problems outlined in the latter half of it.

It’s fair enough for me to be cast as the baddie, sitting here, emotionally removed, making my pronouncements on the lives of others. But perhaps that’s exactly why, two decades later, people are still writing. Advice from a stranger comes with an absence of judgment that’s hard to access from a close friend and hopefully makes the unpalatable element of self-realisation that bit less of a personal attack. If you don’t like what I have to say, you can conclude that I’ve misinterpreted you, or failed to understand the nuances of your situation because I don’t know you. I’m sure on occasion that’s a fair assumption, but on a good day what you’ll get back from this column is confirmation that what you suspect is the reality.

His signal is loud and clear that yours is a platonic friendship

The closer you are to someone, the harder it is not to use your privileged knowledge of them to offer wisdom based on the person you judge your friend to be. Our interpretation of relationships, like history, depends a lot on who is recounting the story. Laying your emotional life bare to a total stranger has to have some advantages. I don’t know you, I can’t use past history against you or form a prognosis based on it and so, in the best of cases, have an unimpeded picture of what’s being divulged.

I answer only what I’m asked by my correspondents and on occasion that causes ire. I understand such misgivings but I also feel that mine is a privileged and advantageous vantage point. Ironically it’s far easier to find a clear path in complicated emotional territory from a stranger than during a night of wine-fuelled confessions with a close friend. Friends are a great sounding board but most of us turn in times of need to the one we hope will tell us what we want to hear.

When you write to me you have no such luxury, but there is the possibility that the process of setting down your dilemma and having it evaluated on that basis will offer confirmation of what you already know, deep in your heart. Friends and family can be compromised by their knowledge of us and although past mistakes can provide great learning opportunities, at other times they merely muddy the water.

You probably won’t like me for what I’m about to say but I’m sure you’ll come to see that there was no other way to read your dilemma. You and this male friend have been admirably honest with each other, which is to both your credit, even if on your part your admission was by mistake. It’s terrifying to own up to having feelings for someone we already know, braving the possibility that the relationship may be damaged beyond repair. He certainly didn’t string you along, which can be judged as either a chivalric or cowardly choice, depending on how forgiving your nature.

Your mate has been crystal clear and I hope you expressed appreciation to him for honouring you with his honesty. Now, time has passed and yet you seem to be wishing it had stood still. When the possibility of a romance has been broached and rejected, the time for flirty emails also passes.

You say this man’s relationship with his girlfriend is complicated, offering that as an excuse for why a flirtation isn’t unreasonable, but it won’t be improved by your emotionally convoluted interchanges. I imagine he’s deleted your conversations because they allude to a form of relationship he doesn’t want with you and doesn’t want to have to justify to her. Either way the signal he’s sending loud and clear is that yours is a platonic friendship and he is otherwise preoccupied.

I know that’s hard to accept and the very nature of love is to inspire hope and optimism in the unrequited lover. We both know that you are lingering when you should have moved on and this man, if he’s to remain your friend, needs to stop being reminded that you wished otherwise. Advice on your PhD is a perfectly good reason to be in touch but not if you’re still scrutinising every word from him for potential weakening of his desire to keep things platonic.

Let’s be frank with each other: if you can’t accept what he is offering then you should be seeking advice, academic and otherwise, from other quarters. Thanks for writing.

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