In the episode Fool for Love, we get the story of Spike's greatest hits ... as presented by unsouled Spike, to the woman he badly, badly wants to love him back.  It's probably more than a little selective.  The challenge:  Spike decides to tell Buffy the real story, with less gloss and glam, now that they're in a relationship and he's willing to be ... vulnerable.  Vulnerable in vampire terms, of course.