If D is the where this ends, then so be it, I will hopefully be a strong and independent father and person when that time comes, because my focus is me and my kids, and not her and her opinions and me thinking about them and why she does what she does.
This is ^^^^^ this good. Read this. Write it down and put it in your wallet.
Oh, and no more long emails. Concise, to the point, business like but with a pinch of kindness.