I finally convinced my parents to go to a Nar anon meeting the other night (my brother is an addict). I was really worried they'd be turned off and shut down if there was anything remotely religious about it. (My dad is a hard core atheist and my mom revolted against Catholicism and can't stand any religion whatsoever now, especially the Christian ones.)
Anyway, they liked it! And I heard a lightness in my mom's voice the day after that I hadn't heard in years. I don't have big hopes for significant change but the fact it brought her some peace was good enough for now.