They were pretty whacked out on drugs like LSD and peyote or dissociated from troubled broken families. You can read her bio here. There was a whole subculture of teenagers and young adults whacked out on drugs doing strange things between 1967-1969 that was surreal to live through. During the trial the subject came up whether her testimony should be considered credible given the volume of mind-altering drugs used. In both the Bugliosi book and in their subsequent testimony, it was apparent they had delusions about Manson induced by the drugs.
Unfortunately, it was not the last time confused young Americans were led to believe a con artist was the messiah. And using similar cult methods. Of course, Manson never got to be president or demand mandatory "End of Life" counseling, actually appointing a "science czar" who wants sterilization drugs in the food and water supply for depopulation. So which is weirder?
That’s right. Now days it’s prozac, etc.