My 88 Year Old Mother Has Been Suffering From What

My 88 year old mother has been suffering from what we think are delusions. She is thinking that things, "bugs" or small "animals", as she calls them, are crawling on her feet and now legs. When this began it only happened after she was in bed for the night. She can feel them but not necessarily see them. Her vision has deteriorated as well as her capability to lift her head and upper body when she is laying down to see her feet. This first started approximately 10 weeks ago. She has been in a home since October last year and since then is no longer able to walk or even stand on her own. We know that she has deterioration of her spine and her feet "don't listen to her brain" as she would describe. She has/had diabetes which they no longer treat (metformin), since about 14 months ago.
Other issues she is having is thinking people are stealing from her. She has been the victim of theft on at least 4 occasions through her life that we know of.
Of all that she is now, with her failing health, my biggest concern is with the fear that she is experiencing with the delusions of something crawling on her. We have also tried to reason with her that it is part of her condition, which she no longer seems to be responding to. Is there something else we should look into? I would love to be able to just help her with the fear.
Thank you so much for any help or suggestions that you may offer.