The look on her face when the Inquisitor tells her Justinia's last words. Ugh! The feels!
I can atest to this. I've just finished the Fade in my second playthrough (yes, the one with the female First to Keeper Istimaethoriel, and YES, the one I've had for over two months now) - brilliant work.
Ugh, marathon bosses are awful! I'm still traumatized by Yiazmat from Final Fantasy 12. 50 million HP! The fastest anyone has beaten that thing is about one hour. On average it takes five. Nothing even close to that in DA games when it comes to frustrating bosses. Even the Harvester wasn't that bad.
Well, the trick would be to just bring Sera and Thousand Cuts the damn thing to shreds.
Like, have a special boost to Thousand cuts, that would actually summon it ten times upon clicking. 550 hits on Tier 3 Focus.
That, or boost Mark of the Rift. PICK YOUR POISON, NIGHTMARE, FOR I AM YOUR VERY OWN NIGHTMARE.
Corinne Kempa did a really solid job with the VA work for that scene, too. Along with the conversation after it, where she's trying to make sense of it all. She sounds so simultaneously confused and crushed as she basically begs you to tell her if she said anything else. ;_;
Warden as a ghoul would have to be one of the fears that attacks her. I imagine that would be particularly unpleasant when they're out trying to cure themselves. 
My feels need a CLS.