Penumbra (Requiem) Ending General Discussion

[Goja]

He could be insane, why not? Personally, i have nightmares that can be compared in term of madness i think (even though it's not same kind)... You can everyone experience it too, i'm sure

The thing is most of the time we forget them partially or totally. If the game was not a dream, then i suggest after discovering that, he killed himself out of despair.