SPOILERS Hallucinating Characters

This is a HUGE spoiler, but we later find out that some of the ML's interactions with another character has been made up of hallucinations. 

This is a minor spoiler as it doesn't affect the plot much, but Haoren hallucinates Chihiro crying and saying things that I think Haoren fears. 

This is a HUGE spoiler, but it turns out the ML is not seeing a ghost the entire time, but he is actually so struck by his grief that he hallucinates seeing and hearing his father, who up until this point was an entire character. 

This is a HUGE spoiler, but the ML ends up becoming diagnosed with schizophrenia and it turns out one of the characters is a hallucination of his.