Noct.

[It's the obvious answer, but with how much Gladio is struggling, there has to be more to it than that. After all, they were the three who knew Noctis the best. It makes no sense that just his absence would have driven them apart. If anything, the memories should have kept them together. But what more could there be? What could have impac-

Suddenly, something dawns on him and he swallows hard, reaching out blindly to find Gladio's arm, his grip tighter than it should be.]

Tell me my blindness didn't cause this. Please. I know I never told anyone what happened that day, but it wasn't anything to do with either of you. I swear this on Noct's life!