Was it because he didn't want the guilt in his heart to seize. Because more than anything at the moment, he had the urge to bang his head against the steering wheel.
And if she wasn't inside the car with him at this moment, he would have run himself to any nearby tree and make a collision.
That way, every pain he would feel might make him feel somehow better. How could he let this happen? He had been the biggest fool in the world for completely three days.
He had been blaming her and thinking of her in every negative way, only to satisfy his jealousy. Not knowing that she was suffering. Not knowing that she had been living through hell.
She wanted to be with him. She asked him to take her away. And hell, he had read things wrong. He had been a jerk and only considered only his emotions.