A non-volatile memory device may include a first wordline on a substrate, an insulating layer on the first wordline, and a second wordline on the insulating layer so that the insulating layer is between the first and second wordlines. A bit pillar may extend adjacent the first wordline, the insulating layer, and the second wordline in a direction perpendicular with respect to a surface of the substrate, and the bit pillar may be electrically conductive. In addition, a first memory cell may include a first resistance changeable element electrically coupled between the first wordline and the bit pillar, and a second memory cell may include a second resistance changeable element electrically coupled between the second wordline and the bit pillar. Related methods and systems are also discussed.