My grandmother who lives with us has started making accusations of abuse. How do we protect ourselves?

My mother is nearing (May 26th) her 100th birthday and lives in our home in an area my husband built especially for her and her belongings. She has been with us for 6 years and is diagnosed with dementia. She is very well spoken and manages to disguise any mental limitations in most casual situations. She walks carefully on her own (generally no assistance) takes her meds when offered and manages to have generally positive interactions at the "club" (our euphemism for our local senior day care). Her Doctor prescribed in home care who assigned a team for her limited care (Shower assistance 2 times each week, RN visits once a week and an assigned minister and social worker who call/visit about every 6 weeks).

Further to the many posts I have been following, she is typically needy in terms of attention wanting to be the center of every conversation (i.e. inserting her wants and needs in a very vocal manner at a recent funeral service for an inlaw and etc.) We know that she needs someone present 24/7 and now that our youngest is home from College for the summer he is very generous with his time as is our 17 year old Grandson. This is a great assistance for me as we operate our own excavating business + on-line Scottish import business and are registered wild life rehabbers with a farm and many wild/domestic animals under our care. We are currently trying to finish a bedroom to help accomodate some of the relatives who will be here for her birthday (not a small task to coordinate).

The problem is that mom is increasingly more hostile and aggressive towards every one close to her. She has thrown her food in my face (too many times to count) and in fact tried to claw (with her intentionally pointed fingernails) what ever she can grab as close to my eyes as possible- she commented to our son at my birthday party _ "it is hard to believe that I spawned that" - very publicly refused a beautiful entree at a restaurant where our son wanted to dine as a special occassion - threw a bathroom shower hand rail at our grandson - anyway you get the picture and I know that too many of you have "been there" too many times. At this stage we try to carry on and accept that this is a result of living to 100 and as sooooo many people tell us we should consider ourselves "lucky" to still have her (another subject for another day).

Apparently mother is not gettting as much attention as she demands so now she has taken a different method to command our undivided attention, The problem is that beyond the tragedy of having our children and grandchild (and the rest of us for that matter) being not only the target of these assaults the CNA informed me that as she was giving mother a shower mom pointed out a bruise (a noted side effect of 5 of the medications she is taking is bruising and she has always been subject to bruises of unknown origin) . She asked the CNA where the bruise came from, mother followed up with "I don't know where it came from but I need to find someone to blame it on" The CNA responded that she hoped she wouldn't be blamed to which mother responded "oh no not you, I'm going to blame someone else". The CNA was very concerned that we be aware of this statement. Mother is at the state in her mental dementia that she typically cannot remember a conversation from 5 minutes earlier but when confronted with this information nearly 3 hours later her quick reply was "that woman who takes care of me knew that was a joke" - mother not only remembered but had a ready and clear excuse. Obviously this comment was very calculated and now I am very concerned regarding the intentional nature of this threat. I cannot feel secure leaving one person home with her as she may in her typical me/me/me attitude accuse that care giver of intentionally hurting her. She told our son (when he was attempting to get her to eat and explaining that she needed to take her meds/food because if she did not she might die) in her nasty & caustic manner "and you would certainly be sorry to see that happen wouldn't you" he was volunteering his time and effort to be sure that she was well taken care of and her comment truly shocked and hurt him..

Now what do we do? Be sure that at least two people are here in order to ensure that no one is falsely accused? We don't have the manpower to do that and I am not willing at this point to live in fear of an intentional attention getting accusation which would jeopardise my family or my home.

PS She has only SS income and the rest of my siblings live 100's of miles away and are not able to assist either with time or money so there is no solution there