She is savable. The neck muscles aren't torn, nor does there appear to be any deep tissue damage from the picture. But, if you want to save her, you'll have to work at it. First things first. Amputate the skin that is hanging off with a sharp pair of scissors. Next, slather triple antibiotic over her liberally This will kill any surface bacteria. Next, take a piece of tissue (kleenex) and cut to fit wound size. Place over triple antibiotic. GENTLY wrap another piece around and tape it in place. DO NOT try to remove later. It will act as a skin of sorts until the skin can regenerate. You will keep it moist with triple antibiotic over the next 48 hours.
Now, for shock. She has to be isolated in a warm area that is scrupulously clean. I tend to use clear rubbermaid tough totes with a heat (chick) lamp affixed to the top. She needs to be kept warm and hydrated. You need to boost her nutrition, so I would recommend Nutri-drench in her water and antibiotic chick feed (24-28% protein).
Finally, she needs meds if she is to fight the infection. You need to get LA-200 and small syringes. Give her a shot of antibiotic (about 1 ML) in the thigh. Use a 1/2 in needle, about 20 gauge. If you prefer to not use antibiotics, you could try Sulmet in the water, but the success rate is much lower.
Also, look at the habitat she was in. This injury looks more like she got her head and neck caught in a chicken wire fence - rather than an attack. Hope this helps.
