WAY too long, way too supplicating. Way too much moral equivalency.
You're trying to teach her. You can't teach an infidel.
You really need to come here for advice BEFORE you do these things. Today -- Confrontation/Exposure Day -- is THE most important day in your arsenal. And you've gone in without guidance and intelligence.
I do know this is incredibly hard, and I am truly sorry you're having to go thru this. It's a BEAUTIFUL letter, CC, and my heart goes out to you.