Molting into the coldest part of winter, unfortunately, is what some chickens do. It's not something they choose, but a factor of their genetics and individual makeup. The pale dry comb is one sign of molt along with feather loss. Good news is the cold weather stimulates the new feather growth.
Often, molt causes secondary issues - starvation, diarrhea, weakness, and even lameness as we've seen in some threads over the past couple weeks. The best thing you can do is some TLC. This means vitamins and extra protein feedings to get her energy level back up and improve her appetite. This also helps the feathers grow back more quickly.
Foods I feed are a rotation of boiled egg, tofu, canned mackerel. You can feed fresh fish, raw hamburger and liver. Usually the runny poop clears up when the chicken regains their appetite and strength.