My disfellowshipped sister has been treated exactly the same way as you. 'Its not about religion, we simply don't get on' 'there are things you don't know about her'...etc. yes rather than expose the craziness of the cult and themselves they shift the blame and the emphasis to the victim. Up until 2 years ago I was treating my sister in exactly the same way. Shame on me for that. I owed her a massive apolagy.
Sorry to hear about how you've been treated. Glad that the truth has been exposed to your extended family. A little bit of justice.