I am an Ascian. My heart's sole desire is to usher in the Great Rejoining.
The look on his FACE. I can't handle it.
You find out that the paltry shade of your dead best friend a/ exists (terrible) and b/ is sustaining awful damage to her essence by absorbing the specific kind of energy which you yourself find most distasteful and painful (traumatizing).
You know they won't be able to handle it—but maybe, maybe they will. You decide to wait and see... because if they can handle the Light... If they're able to actually do what they set out to do, there will be a moment. A moment when all that power is raging inside them, and the world is teetering on the precipice, and maybe they can be convinced. And that moment is impossible, but it's in the future, so you can plot and scheme to bring it about—because if nothing else, you are good at filling an eternity with plots and schemes and looking forward to the moment that they agree with you again.
So you walk beside them, this ghoulish mimic of the hero who you welcomed home after countless adventures. You helped them, as you helped their predecessor so many times.
And then they fail, and the moment they do, someone else tries to force the moment, and you can't live in hope anymore.
You can't pretend that there's still time to find a way to not be enemies.