Given that she is soo young could be one issue. 3 of my dogs were at least 12-13 weeks old before they came to me and my other little guy was only 9 weeks old when we got him and I could tell a such a big difference with the separation anxiety. We had a terrible time with him. He would not sleep with the other dogs for at least 6 month after we got him, He had to be placed in a crate in our bedroom. When we were at work during the day we would leave a TV on. He was placed in an xpen and Iwould give him interactive toys to try and keep him occupied. Peanut butter and treats left inside a kong toy would keep him busy for at least an hour. Over time he became more and more comfortable to be left in his xpen while we were gone. It will get better.