TheParents - first of all, massive hugs to you, and well done on your counselling and taking steps to move on.
Please don't sue your parents. It won't achieve what you are hoping for.
I'm not sure if you discussed this idea to sue your parents with your counsellor, but if you did, did they help you to explore not just your feelings for wanting to sue them but also the potential outcomes and the effects this might have on you? Both if you get the result you want and if you do not get the result you hope for?
I think you really need to consider how you will feel if you confront them and they just refuse to accept what you have to say. I think this is the most likely outcome sadly.
But also, on the small chance they do accept or admit to the harm they have caused you, this might be harder for you than you might think.
If I can suggest reading the Susan Forward books about Toxic Parents, if you haven't already, you might find something in there that helps you with the way you feel.
But also I found a blog that was very supportive to adult children who had, for various reasons, cut contact with their parents. It's called issendai.com and the blogger looks at the behaviour of parents whose adult children have cut contact with them, mostly on on-line forums, and examines how these parents just cannot accept that they might have done anything to cause the break in contact.
It's hard reading, but the blogger seems to have spent a lot of time researching the subject and it might help decide if confronting your parents is really what you want to do, or if you think they will be like the parents on this blog who just can't or won't ever accept what they have done to their children.
Can I also add, that from personal experience I've found that even a negative response to a controlling or manipulative person is still giving them something they want.
They might not be controlling or manipulating you, but they do get to tell everyone else how much you've upset them and, as a previous poster said, they'll be saying things like "After all we've done for her" and "We've tried our best / said we're sorry / don't understand what she means because we never did that" to them.
Getting into discussion about what they've done and the way it's made you feel only allows them the chance to deny it, gaslight you, or throw accusations back at you.
The people I am NC with now keep asking for explanations because they say they don't know what they've done wrong. I've explained it so many times that if they don't know now they never will, so I've stopped trying. They don't really want to understand, they just want to keep the discourse open so they can tell me why I'm wrong.
It's too exhausting. I know they'll never accept what they did, or the way I feel about it, and I know that I can't change the way they act, but I can and have changed the way I respond to them.
Now when they turn up demanding explanations I just say I've already given them explanations and I'm not going to do so again. When they say they don't understand I say that's not my problem. If they try to raise an issue, even if it's wrong or blames me, instead of trying to correct them or justify myself I say I'm not prepared to speak to them. And then I close the door and walk away.
It's brought me far more peace than trying to make them admit or accept anything.
I hope that whatever you decide to do brings you the peace and closure that you now deserve OP.