Heather is right, my 2 silkies would lay about 2 weeks and then go broody almost year round. They can lose a lot of weight. During molting, they may not eat that much. Hopefully, she will get built back up.
Can you try getting her to eat by mixing some feed with water, a little plain yogurt, and some scrambled egg? Poultry NutriDrench or Poultry Cell 1 ml orally each day for several days may also give her a boost.