I remember one from a few years ago that wanted to date me (and more she said). When I told her that it wasn't a good idea (she had a BF), she flew off the handle and immediately went running back to her BF, tears flooding down her face.
Had a similiar situation with a Polka.
A couple years ago when I was visiting the country a business partner introduced me to an architect who was working for him at the time. This young fellow seemed to have everything going for him - youth, ambition, smarts, a good education and a rather prestigious job ( this particular business partner of mine tends to pay good money for good work ). From what I've been told earlier he also came from what was considered "a very good family" in Poznan. Thus it wasn't really surprising that when the introductions were made the dashing young architect was accompanied by a seemingly charming, artsy and somewhat wistful Polish beauty. They really looked like a perfect, well-matched couple.
You can imagine then how surprised I was when said beauty expressed in no uncertain terms a desire to "get to know me better" once her BF and other guests were out of earshot. She made a pass at me roughly 2 minutes into the conversation.
I was pretty much stunned and actually agreed to meet with her on the following day for drinks.
During the night I thought things over and when we met I began to point out certain issues.
"I'm older" - I said. Wasn't a problem for the Polish beauty.
"This could really sour my partner's arrangement with her BF". Well, nobody would find out, she said.
"I live in another country and spend a lot of time on a different continent" Her answer - She can come live with me ( think about it, I've known this woman for about a day now ) and long-distance relationships are workable anyways.
"She has a BF and I don't like to barge in between two people" - She hesitated at that one for some time and then proceeded to tell me she's willing to dump her boyfriend on the next day if I promise to remain "committed" to her.
Holy Bar Mitzvah, Batman! That was precisely when I realised the lovely girl sitting next to me was a total and complete nutter.
Hence even though she made it VERY clear there was a happy ending waiting for me after the date I excused myself somewhat awkwardly and left.
Well, of course it turned out exactly the way You described, Seanus. With her running back to her boyfriend, tearful and all that, telling him what a backstabbing dick I was. Luckily the guy was professional enough that he finished his work on my partner's project before bailing out on us.