@Sir Sam Vimes,
I can give the basic breakdown here:
1. Humans are social creatures, and hierarchical creatures. They compare their own social status to that of others, based on a variety of indicators.
2. Humans want their mates to be of high social value. Preferably higher social value than themselves.
That being said, there are ways that people telegraph their social value. Healthy people are more desirable as mates than unhealthy people. Clothing and other outward signs of wealth increase the perception of value. Etc.
Now, the problem is that when men are jerks the signal is misinterpreted. Being a jerk actually lowers one's value as a mate, which is why the girls eventually break up with these guys. BUT,
acting like a jerk gives the
perception of high social value.
The process (I won't dignify it as a
thought process) goes like this: If this guy were of low social value, he would be pursuing me. Since he is not willing to exert the effort to be nice to me
he must be of high social value.
This illusion/perception of higher social value is why these guys are seen as potentially good mates. Eventually, the illusion fades, but since the process is not a conscious process, the girl ends up falling into the same trap over and over again.