In my short experience... I had 2 of my females do this, one went off of food for 12 weeks and the other went closer to 16. The one that went 12 weeks, I offered her food every week unless she was in blue, the all of a sudden she started feeding again. The other girl on the other hand. I got tired of trying to feed her every week, so I moved her into the rack my breeders are in and a week later she started feeding as normal.

On a personal level I do understand where you are coming from, it is frustrating when they go off of food for a while for no apparent reason. I, personally, wouldn't worry unless she starts looking like she is loosing a significant amount of weight.