My bantam has put herself in isolation and only eats and drinks when I put her in front it the food. She screams when I go in the coop and get near her, even if I haven't touched her. I noticed today that she has poop stuck around her vent and she hasn't laid an egg in months. She just likes to sit on eveyone else's eggs. Is she in pain? Can she be fixed? or do I need to end her misery? Please advise.