Err… the RPG is non-canon. As far as we are concerned and actual lore portrays it, most if not all Helves “survived” not by their strong will but merely thanks to them being carried by Humans et al (no seriously, basically the only confirmed group of Helf exilees before WotLK were the elves from Quel´lithien; and those in Cata quite easily became Wretched when they overfed on a magical artifact. The rest? carried in Stormwind by the humans, or in Dalaran by the humans, or in Hinterlands by the Wildhammer and Draenei, and so on…).
It´s not a terribly difficult concept, but canon wise, BOTH Helves and Belves are still arcane junkies -yup, even with the Sunwell. Sunwell merely gives ALL of them, a passive fix, but the addiction is still present-.