Females hit what I call the "1000 gram wall" and stop eating. For some reason, at about 1,000 grams, they will sometimes quit eating. It's normal, and not every female will fast, but more often than not, that's usually the case. Start offering every other week or once monthly if you feel so inclined.
Monitor weight for extreme losses and ride it out. She will eat again. You may have to get a live to get her drive going again.