To me, this was kinda like when your best friend argues with someone. You see there point and you back them up when they need it, but I think after you talk to them and try to get them to reason. Yes, Buffy deserved to be angry, and scared, and all shouty at Giles and Angel. But I don't think she should have quit slaying by any means. I can see the friend talk now.
Buffy storm outta the library, I, follow.
Me: So, you weren't reeaally serious, right? I mean, just hear me out. no matter what you're gonna die, why not out like a hero?
Buff: Are you saying I should voluntarily kill myself?
Me: No, I am saying that nothing is written in stone. Paper, yes, but not stone.
Buff: They said I would die!
Me: They also said that the movie sucked and it would go nowhere, but look where we are now!