As much as I liked BQ and YH together, my fave was def DH and FJ!
It surprised me because I kind of understand everyone's viewpoint that FJ was similar to Su Jin and the other single-minded crazies. I think where the difference for me comes in is with DH himself. He never comes out and explicitly says "I don't like you, I'm not interested, stop it". There's a big difference between "I don't like you" and "We can never be together" (and he only says the latter much later). YH explicitly, even repeatedly, in all "lifetimes" tells Su Jin what amounts to "I have never been interested in you".
With DH, initially he indulges her "I need to repay you" spiel and lets her stay by his side. When Si Ming and Third Prince help FJ realise that she's actually in love with him and she confesses to DH (in front of an audience...ouch), his only response is "Are you done?...you may go". No "Thanks, but no thanks", instead he continues to let her stay: personally carrying her and sobering her up when she's tricked into getting drunk by Cheng Yu, using his own energy to heal her when she's injured by the untamed phoenix (not even allowing the Medicine King to touch her), etc. Not exactly behaviour that screams "Stay away". Contrast this to YH, who ditches SJ as fast as he can at every opportunity, even going as far as shoving a sword into her chest on their wedding day. Kinda gotta take the hint there.
Even if you buy into the argument that DH is not aware that FJ is the red fox (this is true in the book, but in the drama I think he is aware of it), once she's trapped by the guardian of the Pagoda, he again depletes his own energy to save her. He then gets Si Ming to convince her to leave Taichen Palace rather than doing it himself. Again, no explicit "I'm not interested". Personally, I think that it's at this point that he realises that he's actually in love with her too, so he uses this opportunity to send her away rather than hurting her directly by telling her the truth about the Rock of Three Incarnations.
I hated the part when DH and FJ were in the Mortal Realm, because it was all fake and therefore a lie, but in episode 57 DH himself says that he wanted that time together with her to fulfill his own wish as well, circumventing Fate (and not because he felt sorry for her). Again, not exactly the behaviour of someone who's not interested.
Only once it escalates to the point where she's unable to stay away from him despite him explicitly telling her to, does he finally admit the truth that he's destined to remain unattached for the safety of all the realms. Qian Qian then scolds DH for not rejecting FJ sooner (after FJ cuts off her own tail), which again, supports my argument that it wasn't a one-sided, single-minded crazy "love" like SJ and the others. He gave signals that could be interpreted as being interested and it was only much later that he explicitly says they can never be together.
