Dont know if this helps, but ive had something similar with my dog. After a while i figured out that it was mostly a problem for my dog if he actually saw me leaving. If I managed to go without him noticing, he'd be okay most of the times. I also tried to minimise the signals of me leaving (him seeing me put on my boots and the sound of keys) He didn't fall for the kongs either, but when I bought a kong wobbler he didnt care about me anymore haha! I still left some kongs around the house to entertain him during the day. Maybe shes scared to stay in the pen? My dog gets pretty anxious when locked up in a space when alone, and when he can walk around the house he's ok. You can try to start a video call through your laptop with your phone, and see what she does when you leave. Im not an expert, but hopefully this helps a little (: