I know! I'm just so paranoid about next season my mind is making things up, lol. Honestly, from my perception, I think Dan does still love Serena. If he hadn't found out about her trying to destroy Blair, I think they would have ended up together in this episode. Currently, he's under the impression that the girl he's in love with doesn't exist.
I think he definitely still has feelings for her. He never gave her an answer to her ILY and the look he gave her when she undressed herself was SO longing…