1) Is Bella the only one affected by the Cullens leaving? How has "nothing changed" in their absence?
For the most part, yes, Bella is the only one who was affected by the Cullens leaving. Obviously the hospital suffered and the La Push people were happy.. I was somewhat confused by Bella agreeing that not much has changed since the first day she started there. A LOT for her changed. Unless she meant the other students.. they still act the same. None of them were affected by the Cullens because noone of them were friends or really paid attention to them. In Twilight, when Edward saved Bella from getting smashed, she realized that she was the only one who ever was watching them and noticed them.
2) Why is the dream different than before? Did Bella's renewed contact with Jacob's family change her perception of Sam Uley? How so and why?
Bella's dreams are usually shadowing something or what's going on at the time. Maybe spending time in La Push made her think of Sam. I don't really think her perception of Sam changed in this chapter because nobody talked about him or brought him up. Only in the dream did she see him different.
3) Why would Bella not want to be invisible now, when she wanted to be invisible last year?
She was a new student last year.. She was clumsy and drawing attention to yourself is not a good thing. Now, everyone knows her and how she is, so she doesn't want them not to see her.. I'm guessing she wants things to be more normal and people not stare at her
4) How is Charlie affected by this new Bella? Does he perceive how much of it is Jacob's doing?
I imagine he thinks Jacob is the reason for the change. I don't think he fully believes she's different now and not zombie like.. when someone is lifeless for so long, a few days doesn't make you think it's permanent. To me, it kinda seems like she went from being with Edward all the time to now spending all her time with Jacob.. from one thing to the next. I know Jacob is just a friend, but if I was Charlie,.. I think I'd be a bit more concerned about her getting so "obsessive" with hanging out with another guy.
5) This is the second mention of the monstrous black bear. Did you realize at this point that there was more to it than that? What did you think was going on? Did you think it would turn into what it did?
I think at this point,.. I thought that maybe there really was like this big huge black bear that was wondering close to town,.. I didn't really know about shape-shifters and werewolves at this point. Maybe that the bear was going to just by chance run into Bella at some point down the story.