The code phrase for me is, "What's your day off this week?". I have come to recognize this as someone elses permission to fill up that day with their own agenda. They miss the whole concept of a day off.
I found myself stammering to make excuses and the only time they seem to back off is if I say I have to work.
I intentionally went to a perdiem status so that no one know what days or shifts I was working, now..........I am always working or I am always on call as far as they are concerned. I refuse to carry a cell phone, I am not accessable 24/7.
When I am not available, their tasks and issues seem to get taken care of.
I also put time and distance between me and them.
I thinlk the golden rule is to remember that if we make ourselves available, they will take full advantage. An adult woman like your mother needs to develop her problem solving skills, she should consider why she is being treated horribly and stay and work it out or quit.
People will spend you on themselves.
NO personal calls at work! If your house burns down, you'll know about it soon enough.