Note, again, that White Court "demons" are not yet actually proven to be an independent thing. (Harry seeing something he parses as Thomas' demon in BR is a datum that has doubt cast on it by the WoJ about how what one sees in a soulgaze is subjective; it's not that far away from how he sees Molly's friend's addiction as if it were an independent monster, under the Sight, in PHG.)
It is more than that because all the white court vampires seem to think about it as a seperate entity. That can be something they do themselves to get more control over it but it is exactly the way river shoulders and Harry talk about it in the short story as well.
Say the white court were originally highly specialized warlocks then creating a distance between them and their power serves as some form of isolation to prevent madness just like a mantle creates some distance between the bearer and the power.
But the way magic works that isolation can cause the power to become a seperate entity. Magic makes these things real.
I think trying to decide if the hunger is independent or not is misleading, is trying to draw a hard line where there is not. It might even be somewhat different from vampire to vampire.
Seperate demon or part of the vampires spirit are both ways to describe the situation that are both usefull to describe different behaviours of the same vampire but the truth is both.
Or she could, unlike Harry, be just Lawful enough to figure "a chance to save the entire world, implicitly including my son, from Outsiders" as a greater good than "taking my son away from the White Court" and have acted accordingly.
