She has little enough left after the dragon, and she will not give up the only thing she has left. Pride drives her on, drags her from her bed every morning, forces her to leave the camp everyday in search of work. She will not let herself stop, will not let herself fail her siblings or her people.
Her pride drives her to become what she needs to be, zabadûn rather than zabadinh, though she is ever the heir in direct line. Oldest inùdoy of the king's only son, no matter that she is inùdoyinh, not inùdoyûn. Not nathith, never nathith.
After Azanulbizar, he is Melhekh, with his grandfather dead and father fled. No one thinks of him as melhekhinh, few even remember that once he might have become such rather than melhekhûn. He will have no khuzdinh to wife, nor khuzdûn to give him an heir of his body, only those children his sister might bear.
Her sister bears two sons, two inùdoy who follow him everywhere, and ask after everything. The older more readily understands why he is nadadûn to their mother than nadadinh, though the younger ignores all conventions and says he is just nadad to their amad, and why should it matter nadadinh or nadadûn?
He does not try to explain again, not while they are young, nor when they are older, and both call him uncle, even if the younger forever neglects specifics. He makes both friends and enemies with that habit, and doesn't seem to care a whit what anyone else thinks of propriety.
Even when they follow him on the quest to retake Erebor - to defeat the dragon that stole all but his pride - the younger doesn't both with formality, and the older remembers it well enough for them both. The older is Zabadel, after all, second only to Melhekh, chosen heir to his crown.
The hobbit they take on their journey will not understand why he is khuzdûn, not khuzdinh, so he keeps the strange being at a distance, ignoring him and deriding him. He is surprised that the hobbit keeps standing between him and danger, though, and wonders at it, but even that is not enough to let the hobbit learn that perhaps others might properly call him melhekhinh.
Only in Mirkwood is something said that might cause it all to fall apart, the elven-king using words as if he were she, and frowning when corrected. The elven-king does not understand any better than he fears the hobbit will, and does not take well to the correction. Does not remember that he is khuzdûn, and with every word heightens the risk of the hobbit learning what he must not.
At least when they escape from the elven-king, and are in Lake Town, there is no fear of such a failing. The memories of Men are short, and they do not remember that the oldest inùdoy of Zabadel before the fall was inùdoyinh. No one can tell the hobbit what he must not know.
In the Mountain, though, there he faces his greatest risk when they rescue their hobbit from the dragon. When the dragon calls him the daughter of the son of the king. As if he were nathith, not inùdoy.
"I am King Under the Mountain." He will not allow the dragon to insult him by denying him who he is. He is not Melhekinh, but Melhekhûn, and this is his mountain, not the dragon's.
zabadûn = lord-man (used as a translation for prince)
zabadinh = lord-woman
inùdoy = son
inùdoyinh = son-woman
inùdoyûn = son-man
nathith = daughter
khuzdinh = dwarf-woman
khuzdûn = dwarf-man
nadadûn = brother-man
nadadinh = brother-woman
melhekh = king
melhekhinh = king-woman (not necessarily queen, but a king who is female)
melhekhûn = king-man (essentially a way of underlining that the king is male)
zabadel = lord of all lords (used as a translation/title for a crown prince)
amad = mother