Our 3-year old GSP, Jax, spent his first two years of life living as someone's pet. Then, due to a family change, he went into an animal shelter - not sure where. His adoptors mistreated him and tried to make him a guard dog by abusing him (he has a little nerve damage on one side of his face). Fortunately, he was removed from that situation fairly quickly but the psychological damage was done.
We adopted Jax 3-months ago, and he is blossoming a little at a time, gaining more trust and getting comfortable with his surroundings. He doesn't play with any toys in the house, and only a few minutes with two outside toys. We get a lot of exercise together, and he's very quiet.
Jax pays no attention to the multitude of squirrels we have on our property which has surprised me. Even though he gets plenty of exercise and attention throughout the day and evening, I get the feeling he still needs some type of stimulation. I was hoping someone might have some suggestions on things to try that will stimulate his interest. I believe that every dog needs a "hobby".
How about trying obedience or rally. Something the two of you can do together and he will get lots of mental stimulation as he learns the exercises. My suggestion would be to find a class in your area. It will also help him from a socialization and confidence level. You can also train on your own. Lots of good books and videos out there.
Also, food puzzles like the food cube are good if he is food motivated. And the ever favorite find game. Find something he loves like treats, a toy, etc. and hide it and send him to find it. At first you have keep it easy, but as he catches on you can get more creative in where you hide things. You can also hide yourself and let him find you.
I agree with all the posts, especially another rescue dog !!! I'm sure this would help Jax come out of his shell, Good Luck !!!!!
I don't necessarily disagree with the posts about getting another dog, I have three. However, I would advise that you get him in an obedience class (a controlled situation) around other dogs first. Since he is a rescue you do not necessarily know his background or how he might react. You need to be prepared for that reaction, and a good way to see him with other dogs is in a class. This will help ease him into the interaction with another dog and will give you some insight into his socialization. If he does well, by all means another dog is an option. If not, then whether you want that other dog of not, you have learned something about your dog and can actively address any issues, and you will have a trainer that can help you.