Rose's heart broke for him as he took in the news. She offered him a sympathetic expression and tried to speak in her most soothing voice. It sounded better in her head. "No, the seal...it does that sometimes. She was from a time before you are now. The two of you were already married, but she didn't know about River. But when I said the seal picks and chooses who it brings, it also chooses who it sends back." Which was still a terrifying thought to Rose. One day she could wake up and the Doctor could be gone. Any of them, sure, but what if it was hers?
Before they even started walking again, she'd waved off his apology. "This place does crazy things, I promise you that. Amy's safe, at the very least. And probably quite happy, she missed you loads while she was here." And, as it often did, her heart tugged a bit, missing the Scottish girl. But, well, she had to move on, right? She'd lost the entire world she'd grown up in. She could handle losing a few friends so long as they returned to a time when they were safe.
"By all rights, this place should have imploded when the second Doctor arrived," she admitted with a shrug. "Instead, they all just have arguments about who is better and whose hair is nicer and who had the better adventures. It's tiring, but you get a good laugh out of it now and again." They were close to the TARDIS and she knew there was plenty still to tell him and they couldn't get it all in and she didn't want any friend of the Doctor's (or husband of Amy's, or father of River's) to be in the dark.
She took a deep breath. "Also, we're on a television show. On the telly. It's about the Doctor and his travels and to the people here, we're fiction. And you're some bloke named Arthur and the girls love you. And Amy threatened to kidnap him until you showed up." That was probably the biggest bit of news. Though... "And since it's a Biblical seal and all, and there's demons and, you know, Satan running loose, I'll bring you an amulet from the Complex the next time I come by. It'll keep you from getting possessed. Which is always good."
Okay, done rambling. For a bit. There was so much to say. She knew River could explain more, if he still had questions. Not the Doctor, though. He'd be completely lost.