Have you tried to get her some CBT on addressing these voices. Maybe if she can somehow 'normalise' them then they will impact her a little less. It's an , unfortunate circle, fear tends to make these voices worse and less tolerable.

A basic philosophy that may help , When we accept that these voices are as a result of a brain that is firing incorrectly , then she may find some solace in that. Instead of the notion that the voices are being dictated to her via some super natural force.

Who knows eventually she may see these voices as random , rather than seizing on one word or sentence , giving it special significance and then allowing the power of thought and the underlining pathology to focus on it.