After spending a lifetime trying to understand, among other things, the problem of evil, I have only a few thoughts to offer. One of them is that altruism, as Ayn Rand has said in considerable detail, not a good emotion. Having said that, I’m not inclined to criticise those who wallow in it, as long as they don’t resort to using guns and fear to cram it down my throat.
Another thought is that it’s very likely impossible to pigeonhole motivations. This thread contains a number of possibilities, and most of them may be correct for some individuals and not others. Doubtless some women want the Bad Boy, mixed with, perhaps, other motivations at differing levels. Nearly everyone wants to be valued, and preferably loved. Other women may just have poor self-esteem for the most part, and so on. The human mind can vary rather according to genetic heritage, then further from wildly varying environments.
I regret that I lack the patience to spell out a concrete set of examples, but those with sufficient intellect and education will have no trouble coping with this abstract description. 
I will close by saying that, on the other hand, enlightened self-interest by no means is altruism, and is one of the highest achievements of the man or woman who wishes truly to live in light.
