Spike and Buffy were a given, because I've personally experienced Buffy's S6 depression and my little sister is my world, and Spike affects my sensitivities and personal sympathies like no other male character I've seen. His story gets to me, where his struggle with himself breaks my heart to pieces because he gets shot down every damn time. I'd like to say I identify with him because even after getting shot down in everything he tries, he gets back up and tries again, but I really don't have his perseverance, though I admire it immensely. The funny one was Dawn, who I sympathize and identify with just as I sympathize and identify with my sister. Having the burden of depression is kinda like having the burden of being the slayer (okay, so I'm reaching here), where I get protagonist privilege within my own family because of my illness - and I see Dawn's having to deal with a "special" sister in the same way my sister has had to deal with me. It does hurt knowing I haven't been there for my own sister the way I wish I could, and so I end up projecting those feelings onto Dawn, and being overly protective and solicitous to her as a character.

And once upon a time I promised my baby sister I'd have a boyfriend who'd take care of her just like Spike took care of Dawn. So yeah, it's all a bit muddled.