Hi Learning,
It's me, Seeker, again. I really feel for you, Learning. Really. There's a lot of stuff here to sort through (esp. after having a child, which can really alter a person's worldview). I know Bunny will give you some great insight (and how she is able to do it in just a few words is a special skill!)
Just wanted to suggest that since you don't feel able to free up time/availability to see a therapist right at the moment, you might want to check out the other section of this board "What Helps". Lots of good suggestions. Your stuff is right at the surface and you need ways to deal with it now. Glad you found the board.
One thing I would suggest is something you are already doing in one form on this board: writing. There are studies that show that when one writes about an event along with (this is the key part) how they FELT about that event, it has a very healing and positive effect on the person's outlook. One book I would recommend if you wanted to try this in more quantity in a journal is Louise DeSalvo's Writing as a Way of Healing. Don't get a fancy journal, just a spiral-bound notebook and start letting it rip. Keep it in a safe private place, just for you. You can even burn it afterwards if you want. It's the act of writing it and owning your feelings that counts.
I am concerned that you feel/felt like an accomplice in your father's crimes. I am concerned that you are feeling too responsible for acts you didn't do, and decisions you didn't make. In a way, you were in the same position as the victims who also felt that they couldn't speak the unspeakable and turn your father in. This is a biggie and you need to feel able to give the responsibility for those things back to your big, bad dad. Write it out, say how you felt/feel and give it back to him in your journal. It will help, I promise.
I defer to Bunny on the whistle-blowing part. Perhaps the victims themselves should make the decision, since they may or may not want to step forward.
Hope this helps a bit. Bye for now, Seeker