Sometimes you have to let people deal with their own shit.  D will do it when she is ready - I know from my experience she cannot be forced and neither of us would be abusive to her, and besides she’s an adult.  She has to learn these things for herself, or not.  Don’t be mad a M she is used to an ordered world but would also very concerned for you.  Don’t sweat that stuff - it is her issue to deal with - between her and D.  Just remember the Beavers’ advice - "sway like a gingko flower”, and let others deal with their own issues. You are doing a very good job in my opinion under difficult circumstances. So be proud of your achievements!  I look forward to seeing you all again very soon! That is my ex for you 🙂