I don't know, but as a parent myself, I suspect that detaching and no longer enabling your child is way harder than doing the same thing with a spouse. So I don't pretend to have any insight into the particulars of dealing with an addict child. My heart really goes out to you, because detaching from your child goes against your every instinct as a parent. Which is, I think, what makes it so hard for you to figure out what is enabling and what isn't.
I think the biggest lesson Al-Anon taught me was that what I thought was loving, caring behavior actually was harmful to the alcoholic in my life. That way of thinking was a complete 180 for me. That the best thing I could do for my then AH was to allow him to take full responsibility for his own actions.
Lots of love to you.