The problem with some parents is that for the first thirteen years of bringing up their children they are literally controlling and conditioning that childs behaviour in some way. then suddenly BAM!! that child starts to rebel and becomes more independent and alot of parents go about handling it the wrong way. they dont see it as a positive veering off, instead they see it as rebelling against the parent rather then being independent. certain parents take the role of nags rather then trying to be a positive influence, nagging is more of a guilt trip method of parenting. so i find alot of parents lack people and proper communication skills for parenting to begin with which can then cause their kids to become very bitter and parnoid simply being around them.
I remember when my sister would go out to a party and she was an hour later then what she said she'd be(this was before mobile phones around 1998). as soon as she came home my dad had his bags packed with clothes and threatened to move out and leave everyone, divorce mum. alot of game playing like that and psychologically inflicting guilt upon us as kids happened all the time. Dad was the all conquering leader and you did as he said. every house hold chore had to be perfect otherwise you were lectured for hours.
Unfortunately alot of people who were born in the 1940's/50's have that really old fashioned and conservative authoritarian method of parenting. its the parents from the 1960's/70's who are more likely to be easy going and friendly towards their kids. of course that is generalising but it seems to be a factor in conditioning.
Both my parents had dysfunctional family upbringings, neither had fathers, one left and the other died young so my parents were conditioned and took the role of the authoritarian father figures for their brothers and sisters.
so i grew up paranoid at high school from the bullying then i'd go home and feel paranoid that any miniscule or trivial action would cause my mum or dad to yell for an hour. it was a very negative and fearful environment to grow up in.
however i know that dad has a geat sense of humour and at work around his work friends he is a different person where he feels the most comfortable. he just has temper problems and tends to be arrogant with tunnel vision, people like that are hard to get on with especially living with them, because its his way or the highway sort of thing.