I think it would be better for her, if you brought one of your other ones so she's not alone.
That sounds like a good idea. We currently have a quarantined single chicken in the house and couldn't find her one day when she crawled up to a mirror to snooze next to her reflection. Birds have a flock mentality even if it's only their own reflection. Either get a gentle companion or a mirror for your lone girl. Wildlife rescued a Pelican who could never fly again and by accident they discovered he was less grouchy when he had a mirror to see his own reflection - there were a lot of ducks and chickens and geese in the yard but he didn't mellow out until he saw the "other" Pelican reflection. Flock mentality.