It's a long time ago (history session coming up) but it happened to me about 15 years ago in the old Aquarius in Park Circus in Glasgow. There was a gorgeous blonde girl called Crystal there for a few years. She was very slim, long straight blonde hair, fake boobs latterly and was very aloof and "princessey". The latter is what put me off choosing her for a long time but when I did she wasn't as princessey in reality. I was with her 2 or 3 times and all was well, though can't remember punt details obviously.
Anyway, one day I chose her as normal, or so I thought, and she just said very icily that she wouldn't be going with me any more. That was it; no explanation, nothing. Everything else was as before; the other girls, reception etc.-it was just her. I spent a bit of time worrying about it-will it happen again? what's wrong? am I a creep? etc.-but not long; there's plenty more fish in the sea-especially in those days in the heyday of Glasgow saunas.
I think it just happens sometimes; something, maybe something very personal to them, just spooks them. However, I don't buy this "all women/WGs are irrational" stuff that some guys say; I think it's something everybody's susceptible to if they're in a high stress/ high risk job that's very personal-it just happens.
I didn't try to push it-we just ignored each other in the lounge after that-but I think it could start to go wrong if it happens to you and you (quite rightly in some ways) take offence that you've done nothing wrong etc. and start asking what the problem is.