I wish I had more free time. I fill my free time with dogs, gardening, and photography (photography fits into the first two hobbies). I am an introvert so I do not do much socializing - beyond computers anyway. Any old friends live near by you could maybe get in touch with?
I personally am trying to move more (to lose weight). I don't want to go running per se, I just want to move instead of sitting on my butt as soon as I get home from work. That ends up meaning I clean the house more often. I am trying to cook more. I am walking the dogs more on long walks. That way I am not sitting still for very long. It's better for me. Just for the sake of moving those are things you can do. I think you said you have dogs. Any hiking trails? Take some water, some trail mix, and go on a long hike. I bet there are some sites that list the good trails. Heck, bring a pole and bait. Sometimes those hikes lead to lakes that you can't get to by car.
If you do have a hobby (beyond figs) there are often clubs that run along with them. Fishing and hunting I'm sure have their groups. I don't know if you belong to a church, but there are often socials with those too.
For quiet time to yourself, any books you've been meaning to pick up but kept putting on the back burner? Any projects (be it house chores or fun things) you've been meaning to get to? Try making a list, and start moving.