Serious question for witches/nature religions, please?

My great-grandmother was a devout Christian who served her little mountain community as midwife and herb doctor. She also wrote poetry and ped along to my grandmother, and eventually to me, some of what she called the "old ways" that sounds a lot like spell casting and reading nature omens. I'm trying to figure out, where did the "old ways" come from and do you think she was trying to live in two worlds? She was one of the most whole people I could imagine. Thank you.