For parent/child relationships, where the offspring is the addicted, I would always check out the F&F of Substance Abusers. There are many more on there speaking from the parents perspective rather than that of the spouse. I have always wondered why the "anons" are defined by the drug of choice of the qualifier rather than their relationship to them, because each role brings its own set of problems to deal with.
Success stories are always a tricky area. Don't forget that things have to be pretty bad for most people to search for help on line. Someone with strong boundaries who puts their child (or spouse) out in the earlier stages and the addict gets into recovery is unlikely to ever post on here.
Setting and keeping to a boundary is always much healthier if it comes from a place of protecting you, rather than saving them. And sometimes it is enough for a bottom to be reached. Happy by-product is probably the best way to look at it, heart-wrenching though it undoubtedly is.