He's got a very traditional upbringing.
She grew up comparing who's had the bigger shlong with others.
When she met him, he changed her views of the world.
She started to crave power, because she wanted to make sure she wouldn't be able to taste defeat at his hands again.
Since he's the mc, she's doomed to feel weaker than him all the time and become crazy from it.
That's her life story summarized in five sentences.