You know, none of us want to see our kids suffer and she is like your own but I think maybe at this point, with the circumstances being what they are and her not being a child, that you should just say we are supporting 2 households and can barely afford that so we can't keep bailing you out. If H chooses to sacrafice things to give to her, that is up to him but I think it is probably time to let her go it alone a bit.
If you focus on the past, you ruin the future. You can only live for today.