Sorry to hear that. We probably all have known of a family with a sibling who has this disorder. (I once knew of one such family.) I hope your sibling one day finds a way to recover under the right psychological care.
at this point I don’t think there is anything like recovery there is just living with it....I have no problem with her living as a man . I do have a problem with her thinking that its normal and the rest of the world should bend to this. she will always be a she no mater how she dresses.