Certainly, online posts will mainly be ignored at this point, but for those who aren't totally cut off emotionally and have retained some elemental humanity I do think ground can be made via personal contact, but this can be challenging. When possible I try to just ask simple, unthreatening questions like, "why do you think that? where did you hear that?", etc. . . And if it's just to wedge a stick in the spokes of the wheels and upset them a bit I think that approach can have some effect-- again, as long they aren't too far gone.