destructive dog

Question
I have two spayed female dogs, both from the pound, and each was only 8-12 weeks old when we got them. One is an 11 year old pitbull/retriever mix and the other is a 10 year old Rhodesian ridgeback. The older dog is good natured, quite mellow, and loves to play with my husband or me.  The Rhodesian ridgeback will not play at all with anything. Not a ball. rope or even a squeek toy.    When we got her as a pup, the other dog was about 1 year old,and was so happy to have a companion, that when they would play with a tug rope she would always let the puppy "win". After a few months, the puppy refused to play.  In all these years, this dog has never even accidentaly nipped us.  As a puppy, she was a chewer, and destroyed the frame on the outside of the patio and garage doors.  We replaced them years ago, and had no further problems.  Our daughter was in high school when we got both dogs, and would return home much earlier than my husband and I.  This continued all through college, and when any of us were home the dogs are in the house.  Last July our daughter got married and moved out,and in the past few months some old destructive behaviors are occuring again.  The older dog is not doing any of them.  The younger dog has scratched her way through the wallboard in the garage, trying to tunnel into the house.  We fixed one side, and covered it with plexiglass, then she started on the other side of the door, we covered it with plexiglass as well.  She has scratched a fair amount of the entry door,and has chewed the frame. We have had a screen door at this entrance since before we got her, covered with the metal grates they sell to keep animals from damaging the screen door.  Last week, she actually bent the metal grate,and pulled it out of the frame!  We flipped it over so she would not hurt herself, it was fine for a few days then she did the same thing again.  We removed it, and came home today to find the screen torn and more damage at the bottom of the door.  She really wants to be in this house!

She is never alone,(the other dog is with her)refuses to  play with the toys,and sleeps and eats in the house. She is in no danger of being booted out of the house, she is ours forever, but one of these times she is going to hurt herself. The damage isn't even the key point, but she is obviously unhappy during the day.  It doesn't seem to matter if we are gone all day, or just out for a meal, when the urge strikes she chews or scratches something!  Her health is good,teeth recently cleaned and in good repair.  Any ideas?

Answer
Let both dogs into the house.  Keep them in a space where (if they have accidents) no damage can be done, such as the kitchen.  Your dog is demonstrating barrier frustration.  At her age, she may have some cognitive dysfunction, not something a blood test or health checkup will tell you.  She may also have had some neurological insult (a small stroke), also not something diagnosed by blood tests.  For some reason, she wants to be IN the house, and that's where dogs belong, not in the garage.