How do I calm down my 91 yr old Mom who is delusional?

My Mom is a spunky 91 yr woman who lives alone and drives okay but who has hearing problems and hears loud noises (tinnitus). For years, she thinks phone men are on the poles, men are trimming bushes at night, now she thinks there are folks with hoses pouring water over her fence. She is calling her attorney and neighborhood association. I’m close to her and have always been honest.
Today she accused me of hiding a photo album. I tried to tell her that nobody wants to mess with her. She just cries. This is shooting up her blood pressure. Any ideas?