I was always taught that you stick with them as long as you are able. When I was a kid and a horse stumbled or now that I'm older if a horse bucks, all I hear in the back of my mind is my Dad yelling "Stick with him, Stick with him!!" LOL. You might just want to work on keeping your focus at staying on. It will take a bit of time to retrain your body to clamp down instead of turn loose but you can do it. Most people can tell when they have reached the point of no return in a bad experience and only then is it okay to start looking for a soft spot to land (though I really don't think those exist, I've never found one LOL).