>>568Not OP, but the person you're describing here perfectly matches a relative of mine who fell sick to more or less what you mentioned. It happened over a course of two to five years as it gradually increased in intensity. The person is at a stage where simply taking a walk is a great challenge as they believe every person around them is strategically put there to watch them or to kill them. As a result he/she takes long alternative routes to avoid any and all possible humans in sight, covers his/her face with her hands and even turns around to flee if someone comes too close.
I've found that elaborating in an rational way on how their ill views of the world are indeed ridiculous does not help. Letting the person have internet access amplifies the illness to be honest. YouTube for instance knows what people want to watch, and in the persons case, the site recommends nothing but conspiracy videos about how the world is literally going to end and white people killed by refugee invasions and secret mercenary armies.
Worst of all, he/she refuses any and all medical treatments. As you might've guessed, the physicians too are out there to kill him/her.
I'm unable to help the person to be honest, and what exactly lead to the illness manifesting is not perfectly clear to me. Lack of socializing and very negative formative past experiences are what I suppose might've contributed to it.
>>595From experience, the mental illness follows them, and without treatment and regression of the illness it may get worse.
Mental illness is a really terrible thing, but I don't know how to help. I can only to share experiences.