Looks like a lot of exposed flesh. Was your fish attacked by another fish or did it get stuck somewhere? Add some salt and some melafix to the tank. Do daily water changes until it heals.
She is currently in her own tank with salt, and I have been doing daily water changed, but I haven't used any medicine because I am not sure exactly what it is.
Remove the fish and while holding in a wet cloth pour some peroxide over the area. CARFUL NOT TO GET IT IN THE EYES OR GILLS. Let the peroxide sit on the wound for about 30 secs to 45 seconds then put it back in the tank. Treat the tank with Marycin 2. This should help. Keep the water extreamly clean and maintain the salt treatment.