Secession and the Confederacy did NOTHING to improve the lives and economy of ordinary Southerners.
In the end it ruined them.
Well not after northern states invaded them and killed them. The problem with their lives had nothing to do with the Confederacy and everything to do with being attacked by people who wouldn't leave them alone.
But for a brief period between November of 1860 and March of 1861, their lives improved quite a lot. New businesses were opening up and money was streaming into their cities. All the hotels in their cities were full up and construction was began on new warehouses, hotels, docks and various other businesses.
But yes, if unwanted government thugs start killing people, it tends to make their lives worse.