So Kristen kills her tormentor and cheats on her husband. But when it comes time to confess her misdeeds to a man she trusts and loves she only confessed to the murder. As if to say “I can tell him I’m a murderer but I absolutely can’t let him know I’m an adulterer!”
shareMaybe she felt he would understand her reason for the murder but wouldn't like or understand the reason for the infidelity. Plus she has at least has some romantic feelings for David so she doesn't want him to think she would cheat on him.
shareShe confessed what she thought would turn him against her the most.
If your friend says he cheated on his wife, you’re thinking, “Well you’re a dick.”
But if he says he murdered her, you’re thinking, “Freaking psychopath!” and you call the cops.