Forget the bonding thing and work more on respect is my thoughts.
Horse is not your herd mate, it is a horse, and you aren't its. You signed the check.
Bonding takes time, and at this point the horse has figured out who is the boss and it is not you. And while horse may have trail ridden with other owner, that does not transfer over to a rider/owner that horse has figured out it can buffalo. And that is what is happening here I think.
Instead of heading back to barn and working snot out of horse to teach her a lesson? In her mind she got to go back to barn, the workout didn't enter into equation to her. She got what she wanted, back to barn. That is all she learned. Throw a fit, get to go back. Will be worse next time, not better, and will probably throw fit faster too.
Next time, just sit, when she reaches idiot point. Don't battle her, just sit there. If she steps out in right direction, don't praise at all, just keep her moving, if she spins towards home, turn her around and just sit there. No talking either.
Horses make me a better person.