The first watch (OK, the first three or four watches), I had a much stronger emotional empathy for Spike. He completely lacks the ability to get what he wants from life. Doesn't mean he's not a homicidal jerk, but his suffering eclipsed Buffy's for me almost completely. Buffy was going through a lot, but she had a support system and resources that Spike lacked. Riley might have been just being an optimist, but he was right (I still dislike him a lot). Buffy just needed to hang in there, and she had the strength to do it. Spike had the options of self-destruction and self-destruction.

In future watching, I was much better able to empathize with Buffy, to the point where I now identify with her more than with Spike.

I voted 'Spike' because that was my initial response to the story.