I walk on my own every day in a very rural area - but I have a big dog. I doubt she would do much if a stranger did approach me, but shes enough to put people off and would certaintly alert me if there was someone there.
In your situation OP can you take measures to ensure your safety such as texting someone your route and plan when you leave home, with a promise to update them once you're home safe. That way if you're not back they can alert the authorities and know where you're likely to be.
Then always carry provisions - food, water, and safety basics like a whistle, phone battery pack, high viz clothing, and a storm blanket. That way, if you do have a fall, you can call for help and keep yourself safe while you wait. Your mobile phone is the most important safety feature here. If you're going places with limited signal - consider flares or a safety beacon.
As for stranger danger - as you know the risk is very small, but don't be afraid to listen to your gut if it tells you somewhere is not safe, or if you see someone you don't like the look of. Often we're too polite in these circumstances - if you're not comfortable, turn around and walk the other way.
Also - if you pass people, say hi. They're more likely to remember you if they are questioned about it later.
I wouldn't let it stop you though. All of the above are just precautions. Enjoy the outdoors