Sun Tzu said you shouldn't fight a battle unless you already know you're going to win.
Translating this into dating dynamics, you shouldn't get involved with a woman unless she already idolizes you and will give you a free pass on anything.
In the movie Casino, the character of Ace did everything he could to make Ginger happy. But Ace just couldn't win her love no matter what he did. He was stuck in a "d@mned if you do, d@mned if you don't" situation.
Conversely, Ginger's former pimp boyfriend mistreated her and yet she was in love with him.
The character Ace made the mistake of fighting a battle that he couldn't win no matter what he did. He should never have gotten involved with her.
That's my interpretation of this thread.