She is a young woman attempting to build a life. She may have made promises to her husband, made commitments to an advanced educational program, be on a career track where others depend on her. Healing may mean that her flimsy structure will collapse. She cannot imagine the life that would remain in the debris. It's difficult to convey to a woman who is anorexic that the healing process does not have to be dramatic and extreme.
Healing is a gradual process where each level of experience unfolds when the person is ready for it.
That's one of the many reasons a mental health professional who understands eating disorders is so helpful. Healing is painful. So is being anorexic and living with hidden pain. One kind of pain is endless. The other is in the service of healing and having that healthy life so wished for.