Charlie wasn't herself. There was no real use in hiding that around someone whom she cared about. She knew that Cas wasn't good with most anything human, but it seemed almost as if he was feeling just the same as she had been. She didn't know that it was possible, but maybe eventually Castiel acquired human traits. It had to be possible. Especially with how much time he had spent with the Winchester family.
She knew that Cas could definitely sit in silence for hours. In fact, she had watched him do it many times. It was just part of who Cas was. There was a lot for him to take in that people did on a daily basis, that in all of the centuries that Cas had existed, he just seemed to have a bit of a learning curve. When it came to human interaction, Cas was still basically a child in terms of developmental stages.
Or in some ways was he maybe a teenager?
When Cas finally spoke, Charlie took a deep breath, nodding. She knew that they cared a lot for her, but things were definitely awkward while both of the brothers were on Knowhere with them. The circumstances surrounding her impending death still weighed so heavily on them that they weren't able to enjoy the fact that she was alive and well, right there with them. That did hurt Charlie, but she was sure if they had been around for longer, they would have eventually come around. But now, if she understood how things worked with them all coming to Knowhere from different times and places, that meant that if they were to come back, she would have to start all over with them. She had come to this conclusion after discovering that she had been on their world for at least some period of time after the moment in time where she eventually met her untimely demise. So with that in mind, once someone left Knowhere, they were returned the exact moment in which they had left in the first place. Like as if nothing had happened.
Knowing her future didn't both Charlie as much as it probably should. She was going to die in the near future back in their universe, but she wasn't there right now. Which meant that she was going to enjoy her time for as long as she could.
After giving it a moment, Charlie turned to look at Castiel. "I really do. I'm not really sure how things work here. I don't know if it means that once you are sent home after a time on Knowhere, that you can come back. I'm not sure if anyone has yet. So it's like... do I just sit it out here and wait to be sent home so that I can see them again? Then just wait for..." Charlie sighed, shaking her head. "I'm still not quite over being turned into a doll."