Cas wasn't sure if he got it, only that he found he wasn't sure he wanted to get it. He wasn't sure he was ready to let go of his resentment. It was his, after all. Anger could be a useful tool. It could prop you up. It could keep things at arms length. It could make you feel you were right when you really were anything but.
But it wasn't as simple as mistrust. Castiel trusted himself almost as little as he trusted her to get it right. "I don't see you as you were," he said as if speaking was a great effort. "I... see you as I was.". He sat still in his seat, didn't squirm or fidget. He felt tired but his mind was running, turning everything over as he left his words for her to take in.