Rey doesn't miss that intense wave of hatred emanating from Vader; it feels like something coiling and ready to pounce, and it calls to that same part of her that she'd run from before. The absence of a current threat means she's left teetering on an edge she doesn't yet understand, and she's already fighting a mounting sense of anxiety before Kylo's words break through the haze of warring emotions.

All she can do at first is stare at him, all the color slowly draining from her face as she genuinely forgets how to breathe. She can't make the words fit together in a way that makes sense. It's too much, too unbelievable, and yet somehow delivered with such absolute sincerity that she can't find it in her to deny it.

She looks from Kylo to Vader and back again, trying and failing to take a full breath past the mounting hysteria that finally erupts into a burst of hysterical laughter before she can stop it. There's no humor at all in it; she's nearly hyperventilating in an attempt to catch her breath. But it's so purely impossible that her mind won't even process it, and so she's left speechless as the laughter starts to edge over into tears.