Old trail rider here, now with old horses who prefer to mosey. Back in the day, both were more prone to cut up.
I’ve been dumped a couple (well, more than a couple) times out on a trail. Had precisely one horse leave me and head for the neighbor’s herd one time. She dropped and rolled to get me off. Every other time the horse has stopped and given me that puzzled look that says How did you get down there?
In my experience, a horse you can catch in its paddock is a horse you can catch out in the woods. So Whoa, Stand, and C’mere are handy commands. Treats as well as the phone are good to have on your person.
Split vs loop reins, I dunno which is best. Horse can step on either and break either when it does so. I use both, but usually have a rein extender (aka beatin’ strap) attached to the closed reins, mostly to reinforce an urgent request to get out of traffic or avoid other hazards, and a homemade booma to prevent losing the split reins.
Another nice option to avoid losing a horse is a variation on the mecate “get down” rope. Either use a mecate rein set up on your snaffle or leave the halter and lead rope on the horse, and have the free rope or lead rope tucked in your waistband or belt. You get down on purpose or come off by accident and you have that rope ready to grab.
I don’t have the luxury of consistent riding buddies. If I didn’t ride alone I’d have only ridden about 50 times in the past decade instead of at least a thousand times. Somehow I’ve managed to not get killed, lose a horse, get a horse or myself seriously hurt on the solo rides, and it’s not due to my having nerves of steel, exceptional skills, or saintly horses. You just have to ride the spooks and work through the issues as they arise.
FWIW, old fat arthritic me only gets off a horse out on the trail to pee and only then if there’s a rustic mounting block available. My horses will stand like statues next to just about anything so I can get back on. When my gelding and I were getting acquainted that meant a half hour training session persuading him that the steps of an abandoned house in the middle of nowhere Would Not Eat Him. He’s been really good ever since. Gets a cookie EVERY time he stands to be mounted. Don’t leave home without horse cookies.