Just let her know that you love her and that will be enough. I don't know she feels that way, but she might. Sweetie, there are many children needing a good home. And if you can't have one of your own. You can always adopt. I know you would be a good mother. Good luck with your mom and your family. Never think that you are in the way. You are loved.
Hugs, Karen
PS They are coming up with more and more information on lupus all the time. Maybe they can put it into remission. Never give up hope... Here for you...