Hello Undeleterious,

It does sound like it is psychological due to the neglect. I suggest first though that you take her to see the doctor (GP) and explain what you have here. She needs a physical first to rule out many things, much damage can be done to a growing child if deprived of food and water, both physically and psychologically. The doctor will help you move to the next steps and that should include a child psychologist and a dietitian. My heart goes out to you and your child.