Wow, this is a complicated subject. I do have to say that I was totally pissed off at the bunch of them. Like everyone, I can see where they were coming from but they had no right.
I have seen a lot of comments on things like it being Buffy's house and they didn't have the right to make her leave. That's not the point at all, Buffy did leave on her own. Yeah, Dawn told her to leave but she didn't have to. I think Dawn saying that did push Buffy's decision to leave because, hey, none of her friends stood up for her and her own sister, who she died for, just told her that she didn't want her there. That is hard.
I hated all of the potentials. They were there experiencing first hand what being the slayer actually meant and they really took it for granted. They were there to help, okay, yeah, but more than that they were there to learn. None of them had one little idea what it meant to be the slayer. They may have heard stories about what Buffy had been through, but they could not ever know. From the beginning they had a problem with Buffy, she was the Slayer with a stick up her butt. Faith, Faith was the cool Slayer, the one who was all, "Kick butt, take names later."
Scoobies, come on. There have not been many times when I have been dissappointed in the Scoobies and even fewer times that I have been angry with them. I'll admit, there were a few times when I was furious with Xander (For example when he was sent to tell Buffy to try and stall Angel and instead he told her to kick his ass) but this time I was dissappointed with them all. They had been through almost all of it with Buffy, except for burning down her school in LA, and they know that Buffy always works things out. She may have made a lot of mistakes, and going after Caleb again probably wasn't a good idea right away but they could have said that. They could have talked to her, and not ganged up on her. In this one, I can understand Xander, he was scared. Anya I can even side with a little, her beau had almost died. I was really more angry with Willow on this one, I felt like she was just taking sides with her love interest.
I could go all night on this subject, but it isn't as fun without the rebuttle.