Unfortunately a female can become egg bound with or without a nest box. It has more to do with the size of the egg, how it is positioned inside her, humidity and other factors. I would not provide her a nest box if you don't want them to breed but you may not be able to curb the nesting instincts as they surface and it is better not to try.
Once (and if) she gets really hormonal you will want to take a cardboard box (big enough for her to fit in) and really stuff it tight with chewing material, paper, chucks of wood, pine cones fold the top and bottom closed, no tape of course and put it in her cage with her. Then in one or two sides make a dime sized hole so she see's a place to start then let her go to town preparing that "nest".
If she ever does lay eggs you are better off either letting her sit them if the don't break or you can go on line and buy fake replacement eggs, they don't break and they don't start to stink! The idea behind this is she will sit them for the normal incubation time then realize they are not fertile and abandon them on her own ending the cycle. If she begins to lay and they break or you remove them and throw them away she will think a predator got them and keep laying clutch after clutch which can be dangerous to her and deplete her calcium reserves.
