My elderly grandmother can't hear but refuses to spend money on hearing aids. How can I get her to make the purchase?

My husband and I moved my grandmother into our home a last June. Since then she has had a defibrillator put in, operated on and had removed colon cancer. In Feb. we noticed behavior changes. She was diagnosed with dementia and early onset. She is mean,nasty,verbally abusive and has mood swings. I get no support from my parents who live out of state. I told her that it is time to move and has made no effort to look into places. She does not want to admit that she is getting old (85.) Last week I took her to have her hearing tested and found out that she has a 50% hearing loss. She is refusing to spend money on hearing aids. Any advice?