I think, Shanlea, that something you said rings very true with some parents, and that is they are much better equipped to deal with denial then guilt.
Sometimes however, for our own good, our own validation, and to define our own boundaries, the topic must be broached with our parents. It is NOT healthy to let them perpetuate the lie that we were worthless dying fuckups that deserved a brain washing in order to save us.
The problem arises when we get stuck in the conflict of it.
I believe we MUST state our case to our parents if we want this dealt with effectively, but when do we need to deal with the issues in a way where we don't confront them mostly emotionally, but instead we confront them mostly intellectually, and then once the case is stated and the boundary is set, we hold the boundary only when necessary. Your parents do not need to hear about this everytime you talk to them or at every family gathering. It will only further divide you and them.
Also, don't go to them seeking emotional comfort over what happened, do it in order to validate what you know is true and to set the record straight (so to speak). Chances are they will betray you again emotionally if you ask for complete understanding. They, as Shanlea pointed out, are embracing denial in order to protect themselves from the horrifying reality that they may be responsible for a defining negative event in your life. Countless people, including me, have elicited apologies only to have our parents quip behind our backs that they needed to do commit us to save our lives and then to further justify what happened by denying any knowledge of abuse. I know better but guess what? I really don't care. I have gained the upper hand in the conversation because I have prepared myself with logical arguments and facts and mostly abandoned the emotional teenage argument that ALWAYS failed when I brought it to my father. He is stuck in the emotional argument and we have an understanding now that would never have been possible had I remained stuck there as well.
The urban legends don't just fall over and die when confronted with the truth, they tend to perpetuate in that environment of guilt and denial your parents have embraced.
So, I think if you don't want to feel betrayed again, or over and over again, I want you to prepare yourself to approach the topic with your parents without accusing them, without being overly emotional, and be prepared to argue your points with calm facts, not from the perspective of a teenager.
Also, prepare yourself for the possible train wreck that may ensue. They may get pissed, they may refuse to discuss, they may do any number of things that you don't expect or appreciate.
Remember, the real reason you should do this is to set the boundary....no longer will you let them define who you were in negative terms before they commmitted you to the program..no longer will you let them say they saved or helped you, that you were doomed and needed that "therapy". You know the truth, and you want them to understand exactly how you feel, and more importantly, why.
Good luck to any and all that go down this path.