When they say they did it "for your own good", on being confronted with charges of years of lies and deceit, what they really mean is that they did it "for their own good." Someone making you believe certain things does not lead you to become happy and confident, for it often seems too far fetched anyways. However, it keeps your conduct in line. Once the false gospel has been preached, you had better be converted, and show all outward signs of having believed. It makes life much easier for them, having swept your suffering under a carpet which they never lift, but which suffocates you to death invisibly.
And then one day the game is up and when they show you their cards, you realize that all your childhood, you have brought up happy and well balanced parents.