I remember rather little about the fic I'm searching for.
What I do remember about it is that Buffy, while she is dreaming or in a coma or something, gets transported to Victorian England and meet Spikes alter ego William, and they fall in love.
I think Buffy gets pulled out of the "dream, coma, whatever it is", on the night William is going to propose to her.
She then ends up meeting Spike when he comes to Sunnydale and she of course remembers who he is which leads to craziness I can't remember

ps. I'm sorry if this fic has been asked for previously but I couln't find it.
/weber