My father has delusions that my mother is still alive (been gone 20yrs), he hears voices coming from his truck radio telling him to stop breathing and believes the man that broke into his house was there to plant a listening device when really, he was highly intoxicated and went into the wrong house.

I know he believes someone is after him but I have never seen any evidence to make me think that is true. He behaviour, delusions and paranoia has reached dangerous levels so I have VERY limited contact with him.