I just think since Katherine said 'i love you' while Stefan was looking at her when he was dying in that one flashback in episode 20, Katherine might love Stefan actually. I think Katherine could have used Damon for her more wild side...after all, Damon was willing to love ALL of what Katherine was back then. Also I think that maybe since Stefan was more of a challenge for Katherine, she was immediately interested in him more. Katherine was obviously flirting with Stefan when she said 'I think you play a little rougher' in episode 13. I think Damon somewhere along the way just got obsessed with her and Katherine only made it seem like she loved him. Poor Damon :( I think this might be the case though if what I read from spoilers is true...that Stefan will be most affected by Katherine next season. I believe anyhow even if the spoiler is just a rumor that Stefan still DOES harbor some feelings for Katherine. Why did Stefan keep Katherine's picture for all those years? Why did Stefan's description of Katherine to Elena seem to scream longing? (not to mention his desc. of her was way longer than Damon's) I just think that Stefan isn't aware of it now, but he still has feelings for Katherine. After all, we weren't exactly told Stefan was compelled to love her...we were just told he was compelled to drink her blood and not tell her secret. ;)

I think, like in the books, it's Stefan that Katherine prefers. I also think it's pretty that Stefan will be affected by Katherine's return more than Damon will be.

yeah i agree with katie15. in the books Katherine told them she always preferred Stefan over Damon. and i'v seen spoilers about how Stefan will be more affected by Katherine's return.

I'm fairly certain she's back for Stefan. And i think both brothers will be affected by her but I think/hope Damon snaps out of it sooner so Elena can rely on him when Stefan is confused which will cause SE to drift while DE are brought closer together :)

i think she has a plan for both of them :P

She came back for neither of them, I think. She just played with their feelings all the time, and she doesn't love them. Now she comes back for revenge on something. She surely has some plans on what to do with the both of them. And I'm sure Stefan will be more affected by Katherine, and he's confused, while Damon knows it's just Katherine playing tricks on them, And I hope that while Stefan is confused, Damon and Elena will be drawn closer to each other :):):)

There are 2 possibilites:
1) Katherine came back for Stefan

2) She wants something: (revenge, the device, some mystical doodah that we don't know about, maybe she wants to see Elena, or maybe she just wants to wreak havoc in the town because that's her idea of fun) but it's NOT Stefan. For most of the flashbacks, I wasn't convinced she loved either of them, it just seemed like it was a game to her and she enjoyed the attention of the 2 brothers; nothing more.

I refuse to believe she could have come back for Damon after everything she did to him.

^ i agree about the stefa thing>>>to me throughout this whole season he has been quiet whenever something with katherine came up...and agree with the "i have to know her thing" he thot it was katheirne and i think it was BS when he told elena that u looking like her was not the reason i love u...well u WANTED to know her cause she looked like katherine so stefan is OBVIOUSLY has been lying this whole time..i mean why would keep a picture of her for 100 years...i don't think even damon knew stefan had it until he saw it..
i hope this S/K thing will bring damon and elena closer!

i think more or stefan. and i really wanna see how the scenes wit stefan and katherine will be, i knoe that she wanted him in the book and then he fell for elena...and stuff.

I don't think Katherine ever really loved Damon and that she was just toying with him. So I think Elena might feel bad for Damon and grow closer to him.

what Katie said^^^