Hi Witchontheswitch, I'm sorry to hear about your hen. It sounds as if she has a prolapse ie part of her oviduct has been pushed outside whilst she was laying an egg. Have a look at this, from the Poultrykeeper website http://poultrykeeper.com/reproductive-system-problems/prolapsed-oviduct - does it look like that? The article tells you what to do after you have cleaned it up, and how to lubricate the vent and gently push it back in again.
It's very important to separate her from the other hens, because they may peck at it, and once they've drawn blood they won't stop. If possible, make a barrier of netting or mesh across the run during the day so they can still see each other, so she is less likely to be rejected when you eventually return her to the flock. Feeding a low- protein diet such as plain wheat rather than pellets will help because it will make her less likely to try to lay again for a while.
How old is she? Prolapse is fairly common in young hens, especially hybrids who come into lay before they are fully mature, and also in older birds, again hybrids especially, because they have laid so frequently and well in their first 2-4 years that their equipment gets worn out and slack. Was she laying eggs with soft shells? These are harder for a hen to pass as there's not much to push against, so they make a hen strain more, which can cause prolapse. In an older hen, a full recovery is more doubtful as the same problems are likely to recur.
Just try to keep her clean and make her comfortable, and see how she is over the weekend. Do let us know what is happening. There are other threads on here about prolapse if you use the Search box, and also elsewhere on the internet of course.