I totally agree. Things like these certainly make me believe very little in random encounters. I recently met someone who fits this story (actually, it was the same night I talk about in this post , what a success of a night !). I was about to go home, when a new guy joined the group of my acquaintances. I decide to give him a shot: he has a warm smile and seems interested in meeting new people, not just the women. We chat for a bit and he seems really open and interested to learn more about me. I've recently moved here, so I'm happy to talk to the locals about my first impressions of the country. He sounds clever and articulated enough for my taste, though his proclaimed love for mankind is just a bit suspicious. When in doubt, mention the magic words: my boyfriend. Before I even have the time to finish uttering these words, he's gone. Disappeared. At least, it was quick and painless.

The only thing that prevents me from turning totally pessimistic about meeting new people is this website. Unfortunately none of you seems to hang out in Lisbon these days.

Hi Mia, Layla,
Funny stories.

Layla, you mention dropping the magic words: my boyfriend. But, here is also the reason why men react like this to it. Like you say, you choose very carefully when to mention these magic words, and they're magical in the same way as the magician's poof.

Women don't accidentally mention those words. They choose their moments very precisely. Personally, I found it hilarious to see when they came. I can tell you I've been on dates with women only to later find out they had a boyfriend, or someone saying she was somewhat involved with someone only to later find out they were years together. On the opposite side, just talking to a girl after class, about the class, and all of a sudden these magical words appear. Or even women I said hi to and their reply was, pretty much, hi I have a boyfriend. (A friend told me a case where he said hi to a girl and her reply was something in the manner of: I have a boyfriend, and he earns 100,000 a year, so why would I be talking to you).
Or, in many instances, if I was talking to a girl, and I knew she had a boyfriend, but if I would say something that seemed to her not appreciative enough of her, all of sudden came the boyfriend thing, as if to say: I have a boyfriend so I don't need to care anyway what you think. (Similarly if she was interested in me but thought I wasn’t interested in her).
It's always quite hilarious to see when they choose to mention it, and we all know it is sometimes even made up, but it is always a way to communicate something.

Now you might want to say that many times you need to communicate you are in a relationship so there won't be misunderstandings. That's definitely true, and the sooner the better, but I think it's relatively easy, for women, to do in a way that doesn't mean rejection, if you want to. It doesn't mean the guy wouldn't leave. Maybe he is just looking for someone to date and not to talk to, and that’s perfectly reasonable, but many times they won't.

Of course, mentioning to women your girlfriend is not a piece of cake either.

Hi all,
Mia and Layla, yes, maybe you women have it rough, but you know it's not much better from the guy's side.

I'll Continue Arthur’s point of mentioning to women your girlfriend - you think that doesn't change her attitude? It's even more of the Poof effect. Perhaps she would initially be happier to talk to you, but try to continue the conversation, and meeting them further. I can tell you there hasn't been anything as destructive in my relationship with women as to tell them I'm in a relationship. All of a sudden they don't want to meet you. This is whether they are in a relationship themselves, or not. If they are not, they might feel it's indecent, that it's like being unfaithful if you talk to them, but that's still the easier case. In case they are in a relationship, or even married, it is quite complicated. As long as they don't know about it, they're fine with meeting you, (women usually like being in that place), but the moment you tell them, not so easy anymore. It's not that I think they would be interested in having an affair or something, and then hearing I'm in a relationship it interests them less. Not at all, they have no interest in me (or not much). Perhaps they want to feel I have interest in them, or well, maybe you can explain why. I don't know.

Mostly, I think they don’t understand exactly what it means, and then they prefer not be there. I think it’s the same for many guys – they just don’t understand why are you talking to them if you have a boyfriend already.