River watched the Doctor's routine with the brandy and produced a small smile despite herself. Some things never changed, even when the Doctor did.
"Rather hard to forget," she chimed in quickly, then continued to listen intently. By the time he had finished, she understood completely. In all of her imaginings of what had caused him to flee, unwelcome future memories had not been one of them. She had guessed that it had something to do with the all of the mad things that had been going on. The fact that he left immediately following them had indicated as much. But because he left before she'd had the chance to speak with him--in person, not over the Network-- she had no way of knowing for sure.
As she watched him standing before her, the nervous energy radiating off of him was palpable. She was sympathetic. She really was. She knew how deeply the Doctor felt, especially when those feelings were guilt and anger. But he had left without so much as a word, something she had assumed they had long since moved beyond. And so she was not ready to cut him any slack just yet. She would not press him to reveal the memories. Those were his to share or not. "And you couldn't have, I don't know, said a much? To me? Before disappearing without a trace, save for a suitcase in the place where our home used to be?" There. That was the real issue. Not that he'd run, but how he'd chosen to do it.