Supportive friend now needs same
This explains the dynamic. However, six years of playing by the ring theory rules is a very long time.
Even people in extremis deserve to know that their behavior affects others. Being honest with her is one way of conveying, "You matter." (Walking away, or ghosting her, is a way of saying, "You don't matter.")
You are justified in distancing yourself now, but if you back away, you should also tell her why. This would give your friend a chance to behave differently toward you. For one thing, it might help to preserve a relationship she needs to have in her life. But also -- apologizing to you and asking for forgiveness could soften her hardened heart.
Dear Amy: I have neighbors in my direct backyard who will not leave me, or my family, alone. We have a large, fenced-in backyard and like to spend time outside. Any time we go out with the dog, to do yard work, play with the kids, have friends over, etc., they immediately open up their back door, walk through the gate and come over uninvited.
We used to be nice about it. Now, we're cold, and go back inside quickly until they leave.
They clearly ignore our signals, and keep coming over.
My wife has stopped going into our yard because she is so annoyed.
We cannot go outside in peace without being bothered by them.
They are nice people. I do not want to hurt their feelings, but I would like them to leave us alone so we can enjoy our backyard without being interrupted every time we spend more than five minutes out there. Any suggestions?
-- Missing my Backyard