Aww... well I hope your friend IS back to go for another ride, trail riding is really the best way to explore nature and enjoy it, and I hate to see people miss out on it when they have the chance. I wish her luck.
Trails take a lot of courage and emotional collection, that's my opinion. You're out in the open, or in enclosed areas, you never know what is going to pop up and you HAVE to be prepared for everything all while being loose and at ease with yourself and your horse. I think it may also take a reserve and love for nature, a respect for the things and elements around you; those sorts of people who respect nature are less likely to make the trails less pleasant with things like littering and really just enables you to soak it all in and really appreciate and love what you are doing.
A truly amazing trail horse-and-human team have to have a connection, they gotta be able to read each others minds and know what to expect from the other in given situations. Like Indie... she knows that if something pops out of a brush, or if a car goes blaring down the road inches from us that I may let out an instinctual "scream" or jump and will not be in the situation to be the "boss" for a split second... I just can't help it, I don't even think about it. But she knows that, she's ready for it and she even takes control for just that moment to get out of the way until I regain myself to take the lead again.
Or I know that Indie is scared of steep ledges, and I myself am prepared for that and if I know one is coming up, I put on a stronger attitude and push her harder and know which buttons to push to be able to have her comfortably cross a ledge.
Trail riding (at least more advanced ones) takes as much person-to-horse connection as many high level competitions, and I wouldn't take someone on the trails I go on unless I knew that they either had a horse that would take care of em, or they had that special connection with their mount; I really believe it has a strong place.
Heehee... sorry for the novel, I'm waiting for my pizza to get done and had some spare time to write that monster up
And I see we share the same state!! We should totally hit up on a local ride sometime