She came out here to try and clear the air and make things better, and now she's gone and made it worse instead. "... you don't have to do that. You don't have to prove anything at all." He's already done a lot to prove that he could be trusted. Why couldn't he see she wanted to protect him? Maybe it wasn't fair to keep something so important from him - even if she didn't trust the others, he's been with her longest.