"I--" What is she supposed to say? How can there possibly be any words that would make things right when all she wants is to rip the horrible burden of that memory right back away from him--but that's not happening, no matter how bruisingly she squeezes his hand. There's nothing she can do about something of this magnitude, is there?

"Sorry," she rasps quietly after a moment, her throat thick. Is it an apology for seeing something he so clearly didn't want to share? Sympathy for his troubles? Maybe it's just so he'll forgive her for stepping in closer and releasing his hands only to wrap her arms around his shoulders. "Sorry."