Hmm, reminds me of my mare two years ago!
I don't think she was this hateful, but I was away at college and you would have to ask my dad. He would say "yes". She was very spoiled.
She was green broke but so disrespectful, she wouldn't move under saddle or lunge. I got a tall cowboy to come out and he worked her over as needed. She learned respect for people and only needs rare reminders.
I think the owner needs to hire a trainer for a Come to Jesus Meeting as seen fit. You and that mare will be a lot happier. I think sometimes it is just their personality, but wouldn't write that off for the first excuse.