Hello...as per the what you have mentioned it appears that she is currently having a psychotic episode although more details regarding the illness would be required for proper diagnosis. If she refuses to take medications it is better to hospitalize her, if that's not possible ....visit a psychiatrist and he/she would guide you better on how to take things forward with this.
Next Steps
-Do not force the patient for medications or food ....talk calmly ...tell her it's okay if she wants to cook her own meals
-Try convincing her to see a doctor if she isn't willing to see a doctor with the help of family and friends try getting her to the hospital.
Health Tips
-make sure there are no sharp objects near her
-someone should be around her 24*7 to keep a watch on her
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