[Bro lets out a sigh, already feeling bad that he let his feelings get in the way and cause him to ask that question. Of course Dirk would want to know why, it didn't necessarily mean anything. He supposes that now would be a good time to tell him why she was gone, even if the memories were a little fuzzy. It'd been years since he'd heard the details, and even then it didn't make a whole lot of sense to him.]

She loved you.

[That much he knew was true. He could tell that just from the few times he'd seen her with Dirk.]

I'm sure she still does, because she left with your best interest at heart. There was something wrong with her. She was getting scared... She was seeing stuff and it was getting to her. So she left, 'cuz she was scared she might hurt you.

[The more he spoke, the more it all clicked. All this time, he'd thought that she really was crazy or something. But sitting there in the castle and telling the story, he realized what it must've been. It was Dirk's magic freaking her out. He realized that if she'd known... Well, how different things would be right now.

He realized he could never tell Dirk the truth about it. Not without hurting him, so this is a realization that he's going to keep to himself, while saying whatever he could to make Dirk realize she wasn't a monster. She didn't deserve that. Not really.]