While sports for blind athletes, like goalball, exist, not living in a city and having to rely on cars sounds like a huge obstacle. I have no idea what to recommend. I suppose you already tried the obvious i.e. getting together with other visually impaired people living nearby, forming a club a exploring activities together, but I suppose this did not work due to the low pop density. If you could not find a sighted running buddy who would warn you of obstacles then I suppose there are other problems here of which I have no idea so I should rather not try to give advice that may turn out to be bad.