I agree with everything everone has said. Marta, I cannot believe your mother gave you a balance sheet! WOW. When I finally tried to discuss with my family what went on, they sent me a similar list but without numbers-- it also had "what they had done for me"-- it was really a strange interaction because nothing they said addressed anything I said. Somehow anything they did was supposed to count against any abuse I suffered, even normal parental stuff. We drove you to the ballgame, so it's ok that we repeatedly kicked you out of the house in the middle of the night for no reason. Weird weird weird.
David, this part:
My understanding is that the purpose of a 'confrontation' is to for me to dump their crap back on them where it belongs. My mission is to release and unload as much 'dirty water' as I can for as long as they will sit still.
really really worries me. I think the notion is fine, but it has NOTHING to do with talking to them or involving them at all. When you know that their stuff is their stuff and your stuff is your stuff, not consciously, but unsconsciously, and when you have a really clear idea of how your upbringing affected you (impossible after only three months of therapy, I think) then you will have accomplished what you want. This is going to take quite a long time-- all of us can attest to this. You can't actually dump their crap back on them in a conversation. You can just know what belongs where.
It still sounds like this was her idea, and she got it from one book. That's just the impression I get, and it worries me. It's just all too symbolic. Symbols are great, but not if they bring with them all sorts of potential fallout. And this symbolism seems like trying to give them back the pain of your childhood. You can't give it back to them; it is in you now.
Why is it dangerous and a minefield? Because it will not accomplish what you are wanting it to accomplish. Then you will be faced with doing what will accomplish what you want to accomplish in the aftermath of this horrible confrontation-- I worry that you will be worse off than before, perhaps much worse off. And keep in mind they may not fight back or yell at you. Your mother may cry and your father may leave the room. They may say things that pull at your heartstrings. Some of the things they say may be reasonable. It is not as if they will definitely respond in the way you imagine.
What if it is completely unsatisfying? What will you do then?
Another reason it is dangerous is that it is not clear yet that your parents are so horrible and unworthy of contact that you want to live without them forever. Some on this list have made the decision to do that--- most of those people had TERRIBLE parents who did things like sexually abuse them or who behaved in ways toward them that put them in severe physical danger, repeatedly. My parents are closer to your parents-- problematic, not a great childhood, a lot of stuff for me to work through, including neglect that led to sexual abuse by a stranger. But I am having a child now and am very happy we have been able to work toward a better relationship. They will always have N characteristics, but I do not want them out of my life forever. I have even seen some personal growth in my mother-- now, never bank on that! that is a mistake-- but it has happened and I'm glad we're still in touch to experience it.
Are you allowed to make a different decision than my decision? Absolutely, of course-- I'm just one voice. But please take much more time in making that decision. They will always be there. You can do this in six months if you want to. In the meantime, maybe start to chat with your therapist, and with us if you like, about your life (and your thoughts/feelings) now.
When you do decide to confront, if you do, I would start a thread here about it for tips on what to do and what not to do. People here have lots of experience with successes and failures in that area.