I would have done what everyone else had done. I did NOT like Buffy at all in the latter parts of season 7. She snubbed everyone she ever knew and trusted and decided to act on her own when the entire concept of WHY Buffy was so different from every other slayer ever was that she relied on her friends.
S1 - Xander gives her mouth to mouth or she dies.
S2 - Willow re-ensouls Angel.
S3 - Cordelia and Angel lead the students, Giles and Xander nuke the Mayor.
S4 - Willow, Xander, and Giles all give her their power to defeat ADAM.
S5 - Willow, Spike, Anya, Giles, Xander, Tara all charge Glory to help her.
S6 - Buffy fails, Xander succeeds.
So all of a sudden in Season 7 now Buffy is the ONLY one capable of making the 'tough decisions'? I call serious foul on that one. She was in over her head, she was angry at herself for being taken in by the First Evil, she was acting out of emotion.
I'm not saying she should have taken a vote, but she has at her disposal, three (or more) people who are honest to God heroes. Xander, Willow and Giles are just as much apart of this as she was and for her to not consult them or even to ask their opinion was a sign of her immense recklessness and emotionality.
She was in the wrong, I firmly believe that. Not only that but Xander, the one most loyal person ever in her entire life who has never and will never leave her, betray her, or do anything but love her believed it. That's how you know.