Jyn's composure crumbled completely, and for a moment, she appeared absolutely crushed because she felt absolutely crushed. But she struggled to regain control so that she could give Cassian the attention he deserved ...

While simultaneously wishing she could just disappear.

Stupid, she thought, even as he spoke words that she had been wanting to hear from him, silent and still even as he pushed her hair out of her face and carefully cradled her cheeks in his hands.

She might have whispered 'are you sure' in return, but what she meant was do you mean it and you don't have to say it just because I want it and any number of other worries and fears.