It's an incredibly hard disease to beat. The anorexics I know best both relapsed. One was my age with a daughter.
I'm wondering whether something in the University/Halls of Residence could/should be set up? A resident nurse or MH team? There seems to be the possibility of them not meeting their duty of care given how desperately unwell she was at the time of her admission to hospital.
I knew a man whose daughter had anorexia, and he said that she was the bravest person he knew, just because every day she'd try. She was thirteen when I knew him.