Question concerning possible broody

I think you're right to keep this hen confined for her own safety.  There are a lot of predators who would love to dine on a setting hen and her eggs left alone in the woods overnight.  Sometimes they do survive but I think the risk is really great, it must be more dumb luck or chicken guardian angels that keeps a unconfined broody safe while she sets.

The best way to break a hen of her broody mood is to keep her confined to a wire-bottomed cage set up on blocks or sawhorses so that there's good airflow up underneath her.  It may take up to a week to change her mood.  She may still want to go broody in the future, hopefully she'll choose a nest spot that is easier for you to find.  You could then try to move her & her nest to a safe enclosure and let her set there.

You could also try to make her a new nest with some eggs in her cage, and see if she'll still want to set on them there.  It's okay if you don't have fertile eggs right now, just get her setting on something, you can swap fertile eggs in later if she does.  Try covering her cage with something so she'll feel private, it might help encourage her to set.

Thank you for posting this... another newbie here... I just couldn't figure out HOW putting a broody hen in a wire cage would break her! LOL Now I know! With my current broody hen I just keep getting her off the nest and making her move around. So far - no good. Off to find a wire cage.

I'm new to chickens myself, I was gifted a hen with 5 chicks, she was a great mom, they were at lib all day and went back to their nest box at night.  at about 6 weeks, the hen chased her chicks away from her, then she went to sleep in a tree and coaxed 2 of the chicks with her, looking in one night only 3 chicks roosted in the box and she had made a new nest and laid an egg.
As I understand it, the hen will lay her eggs and leave them alone, laying one egg a day or so until she thinks she has enough, then she'll go broody and sit on them, all day and all night, leaving only for an hour a day to take care of herself.  It takes 21 days to hatch, and this way they all hatch at the same time, they won't develope until she sits on them an warms them....until then, feel free to steal and eat the eggs they won't go bad unless they get dirty.
I mostly watch and learn, but the first clutch  3 were still roosting in the same box, until I noticed a dirty footprint on one of the eggs, now growing in number to 14 - so I closed the box before roosting time and encouraged the young chicks to roost elsewhere, they did.
Now I am counting the days to expect cheeps - by the way, the rooster I had was pretty young, maybe 8 weeks, but definetly saw the consumation, so I'm thinking those eggs are fertile. The rooster came from a green egg and has game bird breeding in part, I'm interested to see what happens.
the other thing is she is so secretive about her nest, I have yet to see her enter or leave, but I don't try too hard either, they seem to know when you're watching.  My neighbor said she wouldn't hatch them, I am letting nature take it's course and she seems to know alot better than me what to do, only I am locking her in at night, from predators I think it's why they hide their nest so well.
I agree to covering the nest, they want to be secluded and away from prying eyes...why not wait and see what happens? make sure she has access to food and fresh water when she wants it - you may be surprized!
By the way, any roosters around in the woods near you?  Life will find a way

Each hen seems to have her own component of broody skills.  Some are more devoted to completing the job than others, some are more easily persuaded to change their minds. 

Some folks will tell you about hens of theirs who disappeared for 3 weeks and returned with a clutch of chicks, somehow managing to avoid predators while they nested.  But it's a real risk, predators hunt at night by smell, and a setting hen is an attractive -- and probably fragrent-- target.