Women are caught between two worlds. According to my theories on how early societies were, the early hunter gatherer societies looked like this:
Women got pregnant and had kids and mostly socialized with other women while raising their kids. Men grew up with mothers but no fathers. When they were old enough, men would seek out male role models and join gangs of men who were the hunters and protectors of the community.
Women and men did not really have committed relationships, but rather men competed among each other while hunting. The guy who brings home to biggest prey is the best and would get the most sex. So from our hunter/gatherer days women are used to giving sex (or getting into relationships) with the guy who brings home the biggest prey.
And the characteristics needed to be this guy are basically asshole characteristics. Also an asshole is more likely to care only about his sexual pleasure during bed and women like this because it increases the chances that he will cum first (increasing the chances of conception). So we have a genetic softspot for assholes. But times have changed and there is no longer any correlation whatsoever between being an asshole and bringing home the biggest prey, also with monogamy his chances of cumming first also do not matter as much. We cannot just turn off our biology though, so we still act the same… unless we are smart enough to realize that it is just biology.
We are getting there nice guys, if it any consolation way into the future we will be more evolved since the present day guy who brings home the biggest bacon is not usually an asshole his genes and the genes of those who mate monogamously with him will be the ones to be passed on. So one day in the future you will not finish last.