Just tell yourself that not just anyone becomes a psychopath. Just tell yourself that it's only a certain kind of person who becomes a killer and that those close to you are not and will never be that kind.
Just tell yourself that you and those close to you are somehow better than those who openly struggle with mental illness. Just tell yourself that you and those close to you are somehow superior to them, that those close to you do not and never will have psychopathy, sociopathy, or any such condition.
Just tell yourself that a devil will never seize anyone close to you. Just tell yourself that it's not possible a devil could enter one of those closest to you and make him or her his plaything.
Just tell yourself that none of those that you've laughed with, hung out with, and exchanged presents with could ever be revealed as a killer. Just tell yourself that there's absolutely zero chance that you'll ever have to look in the eyes of one of those closest to you and discover that he or she had become a monster.
Just tell yourself that, and try to delude yourself into thinking that it's all true.
Narration
Creepypasta story Just Tell Yourself
"Just Tell Yourself" narration by No Time Creepy
Just Tell Yourself- by raidra
"Just Tell Yourself" narration by Soulz Studios (known as Good tails doll on the Horror tales wiki)