She knows she could stab him if she needed or wanted to. But Ellie really doesn't want to. All of her anger is a defense meant to keep her pride and dignity intact. They can't help her in this nightmare. All they can do is let it unfold. The fact remains that she doesn't need his help. She doesn't need anyone's.

"Sick freaks like that deserve what they get."

Her jaw sets and she stonily looks on ahead. She doesn't flinch as she watches herself be thrown hard enough to black out. Any moment now, and David dies. Her eyes look from her nightmare to the intruder. She watches his face for signs of pity. When the sound of her coming to and killing David with as many stabs as possible echoes in the dimly lit room she looks for signs of disgust.