I wasn't sure what to pick, because I do think she would have gone dark and killed Warren, but I don't think she would have tried to end the world. I do think Tara meant more to her, as much as she loves Buffy she was IN love with Tara. But Buffy means so much to her, and besides, it wasn't completely fueled by grief, it was the grief mixing with her addiction to magic. She'd already tapped into the dark magic before then, it was in her waiting for something to drag it to the surface and take over.

I think it would have gone differently though, I don't see her reacting as badly. I don't think it would have got to the point with Willow trying to end the world, I think Tara would have an easier time bringing her back than the other scoobies did too. I think it would prbably end with Tara standing up to her, them having a battle in place of Giles VS Willow, and Willow hurting Tara and the shock of doing that being what brought her back. I can't see Willow ending a world that still had Tara in it.

Yeah, I agree with Asvini..Willow wouldn't gone all evil if Buffy did die instead of Tara. I mean Buffy was Willow's closest friends.. But the more I think about it is that if Buffy did die than Willow would have find another way to bring ber back. As for Tara, she was Willow's everything, someone who had the deepest relationship of Willow than Buffy did. So I am still not sure what would have happen. But knowing Joss Whedon he wouldnt have Buffy being killed off the show again because of Spike getting a soul and that goes along to Season 7.. That we have Spike and Willow who would help Buffy to defeat The First

Ok well think about this, at the end of Season 5 buffy died and she didn't go all crazy but when season 6 came along her lover died, somneone who she didn't think she could ever replace. She knew she could bring back Buffy and she did but then she realized there was no possibly way she could bring back Tara. So, I think she cared for them equally it was just her mind was in different directions.

I took her reaction to Buffy's s5 death into account at first, but I don't know if her reaction to Buffy's death in s5 is an indicator of how s6 Willow would cope, she wasn't in the middle of her magic addiction then. Even then she didn't react 100% sanely, she broke the laws of nature to bring Buffy back without even trying to find a way to check if Buffy was in heaven or hell, so if I mix that with her being in withdrawal from magic then I think she'd have a different reaction. Also, there wasn't anyone there to blame in s5, Buffy chose to sacrifice herself, she wasn't murdered and Glory/Ben had already been killed. In s6 Warran was there to be mad at. And she couldn't have brought Buffy back, because this wasn't a mystical death. I think that loss of control, knowing she was helpless would really affect her at that point.
I think she'd go dark, but I didn't want to pick the yes option, because I do believe Tara meant more to her, and that she probably wouldn't have tried to end the world or even turned on her friends like she did, not with Tara with them and with it being Buffy. I just think she'd have at least tried to kill Warren, Andrew and Jonathan.

I think things would have played out differently. Willow may have gone dark but I think Tara would have been able to bring her back much more quickly than anyone else. I think Buffy means a lot to Willow but in a different way than Tara. Like Asvini said, she was in love with Tara. Plus, not to sound callous but Buffy had already died once, Willow had already gone through the shock and grief associated with that, brought her back and discovered that it was a big fat mistake on her part. I think she'd be more circumspect about Buffy's death this time. I'm not even sure that she'd get so far as killing Warren. Not with Tara there to help her keep a level head.

She cares for Buffy, but her connection to Tara is much greater. With Tara there as an emotional support, she may not have gone dark at all.

I agree with pretty much all of the previous comments. I believe that Willow cared about Buffy just as much as Tara, but she would have had a different reaction to it. Like a few others, I remember when Buffy died in season five, she didn't loose herself completely and go on a killing spree. True, Glory was already dead, but like Tara's death, she could have tried to kill others that weren't really involved, like she did for Andrew and Jonathan. I'm sure she would have been furious and hated Warren (if that's who killed Buffy) but she wouldn't go to such lengths as trying to end the world as I feel her pain would be made up mostly of sorrow instead of fury.

i think vice versa Tara-Buffy i think Willow would have reacted differently and not as extreme and total vengenance and i feel that her addiction to magic would still played a part...but i feel buffy isnt enough to snap willow's self control in her psyche like how tara affected her...so im not sure...how it would have gone if it did swing that way...

Well Buffy is like everyones hero so i think she would've cared for tara more because they were 'lovers'