Hannah Arendt's book on the Eichmann trials is pretty insightful on how ordinary people can commit atrocious crimes. It's because they follow orders and are able to distance themselves from their own moral values. They are just fulfilling their duty and unable to think reflectively for themselves. That type of behavior reminds me alot of the witnesses. Especially if you think about how moving up in the rank and file depends so heavily on adherence to the JW "rules".
I don't think my family shuns me because they see me as evil. I honestly believe they are just following orders and ignore any type of remorse or feelings of guilt because they justify they are fulfilling their duties as Christians adhering to bible principles and that's where the cognitive dissonance kicks in.