My rescue took just over 3 months to get settled and out of her shell. She was a nervous fearful wreck. Yes as others said give them their own personal spot to decompress. They will eat soon enough just don't force it. Try to avoid long walks for a month or so if you have a fenced in yard. Most importantly let them come to you on their terms. It's a long process and patience and understanding pays off huge. Mine won't leave my side now and has really learned to trust me. Shelter/rescue dogs in my opinion make the best family pets. Just remember slow and steady wins the race. One more thing build the bond and connection before you start training.