Thank you all for some great advice! What do you think of Julie Goodnight's training videos?
Last night on RFD TV she had an episode on training a horse with behavior just like Ruby's. All I got to see was the intro so will need to somehow get the rest. She said the horse had been in pasture with other horses, seldom ridden, was fairly young, and *needed to be taught manners*, *not to crowd* the handler. The horse had never been taught how to behave so how could she know what was expected of her. Bingo! This was very encouraging ! Even if Ruby ends up leaving, she may leave with a bit more training.
Now here's a question: Julie's training is done in a corral, and the horse on a lead rope. If Ruby is trained on a lead for awhile, what happens when is off lead, roaming around? Yes, I see the value of fencing her off (but doubt the owner will do it).