There's no explosion of anger, or even a cold shoulder, whatever Rey might have been expecting from him, he can't tell. Just a heavy exhale of breath, accompanied by his arms folding over his chest, with one hand diverting to rub over his face. He has to remind himself, again, that this isn't what happened to him, honestly what she does or doesn't do isn't any of his business, it just feels like it is. He's vaguely aware of how all this works now, and the idea of taking every single version of their war personally is impossible, and regardless of all that there's nothing to be done about the past. She made her choices, whether or not he agrees with them isn't actually all that relevant to her.

He's also aware that he's one of the worst people to talk to when it comes to making a case for Kylo Ren being anything but a lost cause. Maybe Rey doesn't know about his short stint in the custody of the First Order, Finn might not have mentioned those details— and even if he did, Finn wouldn't have any way of knowing what happened before he came along, would he? It hasn't come up, not least of all because Poe doesn't want to revisit those memories.

If he's honest he never doubted that there was still something of Ben left in Kylo Ren, but after what he went through, and after Starkiller, he just couldn't see that sliver of humanity being enough to turn the tide. Rey obviously does.

"Maybe it will. I just hope you get there before the First Order gains control over the whole galaxy. They'll do it without him if they have to."