Re his sister, if she is working an AA program, then she has admitted she is powerless over alcohol (which includes her brother's alcoholism) and works to accept the things she cannot change. She wants to have a relationship with her brother and she understands that she must accept him as he is now, an active alcoholic who has no desire for recovery. Even if she told him he was the worst alcoholic she'd ever met, that would likely not make any difference to him. Also have you actually heard her say this stuff about not being as bad as others? Or is it coming from him? My ex used to love to justify himself by pointing to other alcoholics who were, in his opinion, way worse than he was. So and so went to jail, got a DUI, etc.
Either way, your feelings are valid, even if no one else agrees. I know part of my disease is always wanting to be right,and to have others validate that. In my own recovery through Alanon I am learning to let go of that behavior and to live in a way that is healthy.