If humans believe the elves are forgiving for they live such longer years that old grudges become irrelevant, they most certainly have not met the General of the Elven Force. 
The years have gone by just to ferment the hatred she so eagerly kept growing on her heart for all this time. Her hatred kept her going, taught her to fight, made her join the elven guard, made her pristinely good so that she would take the lead on the war she knew would come eventually. Vengeance is best served cold and she has left it freezing; the dragon that once took her family, her only baby brother lost irreparably in the woods nearby his den, has it coming.