The answer to the question, "Why do women date jerks?" is actually a lot more complicated than one might think.
We're going to have to blame Mother Nature for this seemingly illogical behavior.
If you ask women what type of guy they're looking for, they'll usually say they want someone honest, faithful, ambitious, intelligent, etc. However, what women say they want and what they are usually attracted to is not usually the same thing. Women are attracted to a man's personality above all else, and will use this as a measuring stick of his genetic superiority or lack thereof.
In his book "Sperm Wars", Robin Baker says that humans are biologically driven to ensure their genetic survival. Males want to ensure that their genes inseminate; females want to ensure that they are impregnated by the best possible genes available.
A dominant male personality (jerks fall into this category) is generally preferred over a male that is submissive (otherwise known as a "beta male"). The former is sending an unconscious message that he has great genes and is not afraid of losing the woman by misbehaving. The latter is sending a message that he doesn't think his genes are good enough, so he'll put up with just about anything.
We also need to consider the "Triune Brain Theory".
In 1973, Dr. Paul MacLean, senior research scientist at the National Institute of Mental Health, proposed that the brain is made up of three subdivisions corresponding to three evolutionary eras.
The first, most primal part of the brain is the reptilian. It is responsible for mating and territorial behavior, pecking order, defense, aggression and the emotions of anger and fear.
The second part of the brain to develop was the limbic brain. Love, sadness, jealousy and hope originate here. It controls heartbeat, temperature, blood pressure and the flow of neurotransmitters, all of which are affected by the presence of someone we're attracted to. Sexual stimuli passes directly to it. It is impulsive and instinctual.
It is not receptive to reason and analysis.
The newest part of our brain, the neo-cortex, permits higher functions of logic, thought, language, planning, reasoning and critical judgment.
In "The Emotional Brain", Joseph LeDoux points out that the first two, older brains have a greater influence on the neo-cortex than vice-versa, "making it possible for emotional arousal to dominate and control thinking. Although thoughts can easily trigger emotions we are not very effective at turning emotions off."
This means that the lower limbic system, which rules emotions, hijacks the higher mental functions. It says, "You've found The One". The neo-cortex responds with, "Yes, but he seems to drink too much, I've caught him lying and he doesn't have a job." The limbic says, "I can live with that. He's so handsome and it feels so wonderful when I'm with him."
You can see how even though a woman may say she wants a nice guy, that is not necessarily who she is attracted to. A great example of this is food. Do we make our choices based on what's good for us or on what looks and tastes good? This is what is happening when a woman chooses someone who makes her feel good, but is not good for her.
The solution?
Men need to find a happy medium between being a jerk and a "nice guy". They can be strong and take charge but they also need to know when to be more sensitive and yielding.
Women? They need to date a few jerks to see that the emotional high they get from being with them isn't worth the pain and sadness that ultimately ensues. Only then will they be able to turn the tables on the limbic brain and make a logical choice.