I am not an expert in dog care, and I am still learning some about dogs. But I have a beagle who will poo on our bed if we let him in our bedroom. especially if we leave him home alone that day. I was told that dogs who have separation anxiety do this out of anger for you leaving them alone. my other pup will still poo in the house even right after letting her outside for a while. we just rub her nose in it, sternly shout no, and bring her outside and give her a treat when she goes potty outside. Your problem is not unheard of. I do not agree with the person saying that your dog is showing anger at you because she knows she is a chain all day and feels unloved, for two reasons. 1- it is true, up until recently, it was the norm for dogs to be kept outside all day, many on ropes and chains. 2- Dogs do not have complex emotions like humans do. Your dog does not feel rational thoughts, or talks to other dogs about how much or little their owners love them. they aim to please their owner, simple as that. But there are normal feelings all animals feel. If you leave your dog alone for a good period of time, check into the anxiety thing. I do agree with the person saying we don't know enough... knowing type of dog, age, and how long this is going on for will help us help you better.