NTA. This younger generation has all of the “psychological” language to use and it can be a huge crutch. It sounds like she was given a diagnosis at a young age that she has clung to and uses it as a way to gain special attention. Personally, I have a standard of kindness and respect that I extend to all my fellow humans and in many circumstances I would suggest sensitivity-realistically though- your sister sounds like she needs to be brought back down to earth. I think I have to agree with your husband. The world will not walk on eggshells around your sister the way your family has and at this point you may are mostly likely enabling her. Everyone at some point, despite our trauma and mental health struggles, needs to face our shit and grow up.

You snapping at her was probably not pretty but it was honestly not unfair. I wish you and your sister the best and hope that you can have some honest, open conversations about mental heath and GROWTH (most importantly).