Your gal is doing the same thing as my gal is now. She quit eating around Nov as well and comes out at night as the terror and destroys her cage. I take her out and give her outside time and she just cruises nonstop. Tried food every 2 weeks as well and nothing. Good thing I got 2 garbage disposal boas who eat her rat. I wouldn't worry unless she starts losing weight or you see something seriously going south like stargazing, bubbles/mucous from the mouth/nose, wheezing, stuff like that. I chalk it up to "wanting a boyfriend" like Albert said.