Why is my relation with my parents so bad?

Why is my relation with my parents so bad?
My parents are old revolutionaries.They don't know what love
is and they didn't know how to express the love to others
especially to their children.They ruined my life and tore
up my most beautiful feeling while I was young.I lived
with the din of quarrels and curses through my childhoo.
I hated them.but so many people didn't understand me, saying
It's my fault.Don't tell me that I should do duty to take
care of them.I have no heart because it seemed they don't
deserve being treated like that.For most part of my life,
I've undergone an unhappy life they brought.I was treated
like dirt.What they did was very selfish and imprevious
to reasons.The net friends always criticize me as ungratful
being.but I don't agree with them. I have so many reasons
to write them off.My question is whose fault the hell it
is.Shall I distance from them rather than bear their
wrongdoing.
There is a saying that you sow beans and you get beans,
you sow nothing and you get nothing, your wrongdoing
will be paid off in the end.Why does the axiom apply
to the evil person and does not apply to my parents?
I just want an aswer to me, to my child and even to
my grandchildren.