What do you do when she spooks or bolts? Do you stop and look and halt and then walk slowly or do you pretend nothing happened? Are you tense and waiting for the explosion? Try to find a way to ride loose and try to exude confidence. If you see no danger, she should start seeing no danger. If she looks at something, that's ok, let her look for about 3 seconds and then carry on. If she spooked at a horse eating imaginary foe, then pretend it wasn't there and go about your business. And agreed with the long rides.