Okay.

[He tries to process. To add things up together and sort them in his mind. He gestures vaguely in front of his face with both hands in circular motions.]

This stuff. That I could be from after liberating Derdriu and you're from Fhirdiad several days before. That people leave and come back and sometimes they don't remember. That it happened to Dedue. That there's apparently a lot of us from Fódlan who are here.

[He breathes in deep and then lets it out slowly. He'd forgotten to breathe for a moment, too busy thinking. His chest visibly expands and deflates with it.]

I want to apologize anyway. Because it has to suck. I know if I were in your shoes that it would suck. I wish I remembered. I wish I hadn't been gone so long. That's all I'm trying to say.

[He doesn't necessarily blame himself for the fact that he disappeared, but Felix doesn't need to know about the little toothy guilt monster that's gnawing at him.]

Well good thing you didn't, because then I would have come back and you wouldn't be here.