I am usually on the Arthritis site but read here constantly because of pain (of course0
I just had to respond because of my story.
My parents are dead now. But years ago my mother developed bipolar issues and accused me of many things, theft, etc. Called me constantly many times a day. My dad and brother knew she had problems but would attack me when she complained to him as if everything were true
It broke my heart and I tried harder to be a dutiful daughter. Didn't work. Weeks/ months would go by that she would not speak to me.
I shared this with a friend and she suggested a psychiatrist she respected.
It was wonderful! As a professional I was able to accept advice from him that I wouldn't have accepted from a friend .
He told me not to be so readily accessable to them. Do not answer the phone let it go to voicemail. And return the phone call when I was good and ready. Limit physical time.
The biggie though was that he gave me permission to go through the motions of being family but that I should look for another mother and family for emotional health.
i did that and it saved my life. It took awhile to do this but as I told him it was fun to look at others and think of the qualities I needed and could they give these to me.
I think you have done some remarkably good things, door locks etc. but if it were me I would never invite them to a meal again and never go on a trip with them. I have meals and trips with my other mother and family. ( they know by the way) Once on Mother's Day my other mother called and said Happy Mothers Day from your other mother