Attraction to people who get by on superficial charm does tend to fade when the source of charm is removed. And love has nothing to do with "who is the better person".And yet she had to force herself on him after he rejected her by saying he had real feelings for Elora.
Now, Elora plays with the flute of the guy who actually did turn on the rest of the party earlier in the show. Apparently, that's forgivable but being held captive, drugged with weeks of worm juice, and magically brainwashed is held against Airik.
Not to mention that Airik's natural impulse was to try to save Kit (when she fell into the wormjuice lake) even when he was in the personal presence of the Crone.