I don't think there is a single "Southern way of life" since the South is a pretty big place.
I'm not particularly interested in history, but from the little I paid attention, the part I grew up in was too steep, rocky, and poor to have (any?) slaves. What we did have was a large number of Scotch-Irish who have a strong tradition of:
- insularity
- contrarianism
- hardscrabble self-sufficiency
- anti-authority
- love nothing more than maintaining a good feud
- religion (protestant roots)
- loving "the land" (hunting, your farm, etc.)
Ignoring the morals of the situation, from an economic perspective the North could afford to give up slavery. They were richer and their more industrialized economy wasn't based on slavery. The Southern economy was (completely?) reliant on slavery, and when the Northerners legislated their economy away the rebellion was somewhat predictable. Painting anyone involved as a racist is easier and true to a large extent, but there were strong components of "don't tell me what to do" and just not having any viable economic alternatives that also contributed.
In my mind at least, a lot of modern day Southerners of a certain type (the poor white trash type, not the Gone With The Wind aristocratic plantation owner type that doesn't really exist any more) just love telling outsiders they can fuck off, and waving the rebel flag/preserving statues are pretty handy avenues for that.