From what I understood, Margaret had been planning for her own death, and coming once a month to the Dollhouse to have her brain scanned, so she could be brought back. (It's more than likely that she paid for the privilege, meaning that Adelle wouldn't have been using the Dollhouse for her private purposes).
I liked the parallel between Adelle in the previous ep and Topher's in this one, especially as Topher didn't use Sierra for a sexual purpose.