There's an instinctual shift as Dean comes barrelling in. The kind built into having other people at her side, back, and vicinity. She has, off and on, even across the last few years. More alone than not, but still every once in a while, when paths crossed or cases aligned. And then with her Mom when she showed up, again.

For all of a breath, there's the sturdy deep relief of having some backup, someone at her side, as she's stepping to one side, and then Dean throws the whole of that right out the damn window. Not at her side but getting in front of her. Telling her to stop. Telling her —

"What?!"

She could not have heard any of that right.
Any part of that, every part of that, was ludicrous. Wrong.