Curious why you feel the need to DA? I've faded for over 7 years, and my mom still talks to me.
Yeah, I was wondering that myself RIchie? Less heartache for mom, you still get to talk to her, and since you still get to talk to her you are able to help her have a different perspective.
I guess it doesn't have the closure or finality you might want. I think that dramatic crap is overrated. It's the small, simple, unspectacular things that will improve your situation over the long haul.
If you do feel compelled to go through with your terribly thoughtful, clever, and wise (beyond your years as usual) plan I would make a few suggestions. Remember, the fundamental rules when talking to a person under mind control:
1. Never attack the org.
2. Ask honest, genuine, and humble questions that encourages and challenges the person to have a different perspective.
3. Emphasize your decision to be a matter of conscience and a desire to be a good person, not out of a desire to be sinful. (Hey it might not be true, but assure her you won't be dating strippers. It is good to tell these lies to your mother.)
4. Make sure to tell her how much you will always love her, no matter what. Conditional cult love loses to genuine unconditional love EVERYTIME!
Take those comments that align with those fundamental rules and present those to her. I think the ones you want the most are the ones that just talk about how much we admire your wisdom, wit, and maturity without mentioning those qualities in the context of your opposition to the org.
Take care bro. Everytime I read your stuff, I am bummed that we didn't go through that "real heavy drinking and puking" time of our lives together. Mine is long past. Yours isn't even here yet!!! Good times!