Getting a horse comfortable with hacking alone?

Haven't read the whole thread, but have you tried having someone walk with you on foot or a bike, taking it in turns going in front? That's helped some of the issues I've had in the past :)
 
Are you competent at long-reining? If not it's a great skill to learn and can be really useful for nappy horses as you can drive them forwards from behind. It is great for teaching them to go it alone yet you still maintain control.
 
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