I've seen Alanons invited to speak at an open AA meeting (and I've only been to 1), it was a "chip meeting" where someone was getting their 30 year medallion and we (the Alanons ) joined with the AA folks.
NerdlyBeauty, totally get where you're coming from. I left when my son was 4. He is 5, will be 6 in a month. You have done all the right things, as far as age- appropriate explanation. My son has literally never asked about his dad (reading your previous posts, I think we were in similar situations as far as the abusive behavior). I say "it's Father's Day/Christmas/Whatever holiday, do you want to send Daddy a card?" and our son loves to draw pictures and write, so he does.
But otherwise, he never asks about daddy, or says that he misses him or anything. He dislikes speaking on the phone because my ex rants and raves and goes off on paranoid tangents, but since we've got a custody thing going on I make sure they talk every Sunday. Stupid, but I don't want to get accused of parental alienation.
He saw his father's drunken, abusive behavior for four years and is scared of him. Never asks me when he is going to see daddy or says he misses daddy. Not once since I left.
He is much better off. Has blossomed and grown more confident because he's no longer dealing with my ex's crazy behavior.
PM me anytime. Big hugs to you and your son.