The dilemma I am a 20-year-old woman who has been dating a guy three years my senior for the last three months. We became official and he introduced me to a few members of his family, as well as suggesting we go on holiday together in a few weeks’ time. This is my first real relationship and I was excited by it and him. However, recently he mentioned how his initial impression of me was that I was a “slut” because I was willing to sleep with him after three dates, and he referred to me as his “slutty little girl”. He has mentioned that he does want to sleep with other women, although not when we are dating. Since he said that, I don’t find myself getting excited about hearing from him or the thought of seeing him again. In fact, it fills me with slight dread. We have become very comfortable around each other and spend most weekends together. But sadly I have even begun to question if I want to be in a relationship at all. I am starting to feel like an imposter, and I’m not really sure what to do.

Mariella replies May all girls be blessed with your good sense. As you have gleaned, you’ve been cast in a role you don’t desire, based on entirely outmoded assumptions about female behaviour and made worse by what it reveals about your lover’s peccadillos.

It’s so long since I heard the word “slut” used without irony, or humour, that I decided to look it up. I don’t want to turn into one of those professionally angry feminists or Brexiteers who start railing before they’ve reached the second syllable of a differing opinion. The definition I found bore out my suspicions: a) An offensive term for a woman thought to be sexually promiscuous; b) An offensive term for a woman who charges for engaging in sexual activities; and c) An offensive term for a woman who is regarded as not concerned about conventional standards of domestic cleanliness. On all three counts you’re absolutely right to be offended.

He may not have stopped to think how Neanderthal he sounds

If this were a bedroom game he’d invited you to collude in, there would be a choice about what you find stimulating. What happens willingly between two adults can include all sorts of words and deeds that, scrutinised in the wider sphere, wouldn’t live up to the expectations of righteous moralisers. The human imagination and the sexual fantasies it inspires are not something you can proscribe – you can only ascertain how far you personally want to get involved.

This boy, however, isn’t even giving you the option of mutual consent. He’s defined you exactly as he desires to imagine you and that’s what’s really offensive. Even if you’d jumped him on your first handshake, demanded he showered you in pound coins afterwards and then tipped your dinner all over his sofa and refused to wipe it off, calling you a slut in anything other than ironic jest or consensual sex fantasy is entirely unacceptable.

Your story is enough to drive me to despair. After 35 years of battling to be judged and treated equally – 100 if you go back to the suffragettes – there are still idiots out there who fail to understand that there is neither justice nor a future in maintaining different standards for men and women. It’s so boring to have to re-tread the same ground and listen to unreformed nonsense from men (and sometimes women) who in a #MeToo world no longer have the excuse of ignorance.

I’m sorry you find yourself with a man who doesn’t deserve a girlfriend, let alone an astute one like you, on your first relationship outing. At least it’s an early lesson in why they say, “You have to kiss a lot of frogs before you find your prince.” Happily, I think you have the potential to cut to the quick if you carry on displaying such a highly tuned sense of what is unacceptable or inappropriate. You have all the time in the world to hook up with a guy who’s grateful to have found you rather than already warning you of his appetite for further conquests once you and he are done. My advice would be to tell him you don’t want to delay him in his search for further trophies to his seductive prowess. You’re more interested in a man who wants a woman, not a cliché seeking confirmation.

Just finally, and partly in his defence, the regression to attitudes and assumptions that last blossomed without censure in the 1970s is increasingly being linked to the proliferation of pornography. Many people your age glean their sex education from porn films, easily available online, that are positively Jurassic in their outmoded depiction of thrusting men and objectified women. These films rely on narrow definitions of gender identity – that men are all-conquering and women can be divided into the marriageable and the slutty.

Your boyfriend has most likely had his brain polluted by such propaganda and may not have stopped to consider how Neanderthal it makes him sound. If you really like him in other ways, it might be worth attempting to explain why you find his assumptions objectionable and allowing him a right to reply before you move on. Personally, I’d be making alternative holiday plans...

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