My mare used to rear, mostly when afraid to go forward, sometimes when in a
snit. What worked for me, I learned this completely by accident, is that
when you feel her getting light in the front end, push on her neck with your
hand, and tell her walk on.
I think it works because when they are refusing to go forward and/or
getting ready to rear, they lock up their neck. By pushing on the neck (It
surprised her the first time) it unlocked the neck, and she went forward.
It was accidental, as I was really trying to push off the neck to avoid having
her head smack me in the face (which she did once before). Now it's a cue,
that she learned unintentionally, to unlock that neck, soften it, and move
along.
