Thank you so much! I'm so glad to hear you liked it😁
(Lore Spoilers Ahead)
As for that lore bit, there is a lot of hidden details throughout the notes and other reading in the game that all come to the conclusion that the Rowan Walker(aka the player)'s brother died and that the grief drove him mad/insane. In the good ending, when the player finds his brother's grave he comes to reality and in the end decides that he really does need help to get over his grief. Rather than the alternative, since in the bad ending he ends up shooting the monster (actually a asylum staff worker) since he is hallucinating and when he gets to the grave the grief overcomes him and he ends up offing himself when the police arrive to arrest him for the asylum staff worker's murder.