Have every pastor remind their congregation about the joys of sobriety, hard work, faithfulness in marriage, and caring for children as the aim of life, not "living life to the fullest".
The alcoholism epidemic of the early 1880's was largely stopped because one brave pastor, seeing the deaths and family disintigration, decided to preach on it, and the movement spread.
But of course, people now worship at the church of TV. And a drugged up/drunk population become sheep easy to welcome a nanny state that will remove the need for personal responsibility.
As for rehab, it only works if the society changes. Nowadays, they come home from rehab, and the local crack houses are still there. And don't fool yourself: Meth and crank are the REAL problems in the bible belt, and usually polypharmacy is the rule.
We'll never succeed on the supply end, IMHO.