"Your parents love you more than anybody in this world, since you were born, they devoted all their life to you. They don't want to hurt you"
even in cases where there is no physical abuse, drug problems, etc., there are plenty of families in which parents are not devoted to their children, do not love them more than anyone in the world, and would not do anything for them. people which such parents are very lucky, because such devotion and care is not as widespread as you seem to think it is. some people, parents or not, will never be even slightly selfless or capable of loving anyone more than themselves. your generalization is quite ignorant, although im sure anyone who lives in a happy, loving family would have trouble imagining that there are others do not live such a life.