I've never had a problem with my cats stopping eating, no cat that has ever been in my home or my parents home did this.
I personally think it's good to give them a little variety.
What brand of food are you feeding her right now, and is it dry or wet? Lots of people switch their cats food brands after a while, I think it might be a good thing, and it also gives you the chance to find a food your cat will thrive on.
I used to feed Authority, and every 1-2 months I would give them the chicken and rice, then in another 1-2 months they'd get the lamb, and then the ocean fish... etc etc. You get the idea.
My cats have been on Solid Gold dry for about 3 months now maybe longer, they haven't gotten sick of it. But they do get various wet food brands every 3 days for a little extra something something. And sometimes I'll give them treats of other food brands. Like small food samples I'll receive.
Keeps it interetsting for them.