Give your hen multiple sources of calcium and mineral blocks. It will keep her healthy. Second, leave all the eggs she lays inside the cage for her to play with. They cannot be fertile since she has no mate. Let her play with them and keep them, removing only the ones that break or leak or stink. Egg shells are NOT air or water tight and the eggs eventually dry out and can be used as dud eggs in the future to help limit the number of eggs she produces. I practice fertile egg removal birth control with my birds; checking for fertile ones and removing them before the hens and cocks can hatch them.
If you want to give her a flock mate, decide if you want a hen or cock for her companion. Hens get along better with one another and you don't have to worry about fertile eggs, but cock birds allow your hen to have a mate and be happier, in my opinion. If you don't want babies, you will have to remove the fertile eggs before they hatch.
Cockatiels, budgies, most parrots, live in flock groups which are made up of mated pairs. They enjoy the company of birds of their same species.