death of an uncle, grandma is crazy

My grandmother's brother died on Monday. He had a brain tumor, similar to the one afflicting Senator Kennedy, and got it around the same time as the senator.
I'm not sure exactly what happened to my uncle. He had been in bad shape as the tumor progressed, and he was placed in a nursing home in the last few weeks. The nursing home moved him to hospice about a week before he died. But there is so much denial and misinformation floating around in the family--supposedly the hospice was temporary and he was getting better and about to be sent home? That makes no sense to me. And everyone seems so absolutely shocked that he died...a man in his 80's who had been fighting a brain tumor for over a year, maybe even two years.
Seeing my grandmother's reaction to her brother's death makes me really question her sanity and yet I can find no signs of dementia in her, unless she is progressing in a completely different fashion than my dad. She complained throughout the wake about "how hard" it was for her (to sit in the chair? To see her brother dead?) and as usual made it all about her. She refused to come to the funeral; my mom and I went as her emissaries. Nothing I loves better than a high Catholic funeral mass on a Friday afternoon to raise my spirits, followed by a military/Naval funeral rite at a windy cold grave site.
I wasn't at all close to my grandmother's brother--I maybe saw him once a year. His children are all 10-15 years older than me and their children 15-20 years younger than me, so I'm not close to them either. I wouldn't recognize his grandchildren if they were seated near me in a restaurant. I couldn't pick them out of the wake/funeral crowd for the most part. So I didn't grieve or anything, although I cried just because of all the emotion in the air, and being so damn empathic in situations like that.
The most noticeable symptom of my grandma's craziness (for lack of a better word) is an utter absence of hygiene. She doesn't change her clothes (including underwear) more than once a week unless my mom forcibly takes the clothes. She now only "washes" once a week. I use the term "washes" loosely as she doesn't take a bath or shower, just wipes the "dirty" parts of her body. I can't go more than 2 days without washing my hair/body because I feel disgusting, I know I smell disgusting, and it's physically uncomfortable. I don't know how she does it. She never, ever washes her hair, which is plastered to her head with grease and is enough to make a person want to vomit. My mom and I have said we'd wash her hair in the sink or take her to a hairdresser once a month to get it washed and she refuses. I said I'd get her dry shampoo (like powder) and she refuses to use it. How do you reason with a person who is filthy? I hate sitting next to her at meals.
I've spoken to some friends who are nurses and they've made suggestions to try to help my grandma. What would be ideal would be to have someone come in once a week and scrub her head to toe. But Medicare won't pay for that. She is utterly non compliant in all medications, so even if we can get her diagnosed with depression or something, she won't take the pills assigned to her. She refuses to take any medicine because it makes her "sick" and gives her "die rear" (how she insists diarrhea is pronounced) and makes her "dizzy".
Her other personal habits are just as annoying & gross. She makes herself coffee, pours milk into it, drinks a sip, then leaves the almost full cup on the counter. A few hours later she microwaves it, drinks another sip, leaves it on the counter. Eventually, after a day or so, she has finished the cup. She pours new coffee into the filthy cup and starts the cycle again. I want to gag when I see her doing it. If my mother dumps out the putrid coffee and washes the cup my grandma gets angry. She's got all these rules which she invented. The other day I was over there mid-afternoon, downstairs with my mom playing video games. My grandma said she wanted bread and cereal (the pantry is in the basement)--no hurry. An hour later she's at the top of the stairs yelling she needs her cereal and bread NOW! Why? So she can lay out her breakfast for the next day...at 4 p.m. the day before. I don't get that at all. My dad did it too, only he didn't lay his out until around 9 p.m. which isn't bad. But it's not like it takes forever to get out a spoon, bowl and box of cereal in the morning, esp. if you are retired and have no pressing engagements.
I went for a long walk yesterday with a friend whose mom is in a nursing home and getting dementia and we talked a lot about how hard it is to deal with loved ones who no longer have any logic to how they do things. My friend paid her mom's rent for 18 months because her mother insisted she was going to come home--even though the doctor said it wasn't happening. She took in her mother's pets and visits her mom daily, only to be showered with invectives for never visiting and not caring. Now her mother is demanding an expensive funeral spread over 2 states (she is no where near dying, just making her own plans). The mother has no money or life insurance policy to pay for a such a thing, and her daughter is already in debt from paying her mother's bills and partially paying for the nursing home for 2 years--and the nursing home is coming after her for MORE money, even though there is none.
These are the real stories of dementia--add in my friend whose grandpa has dementia and MRSA and there are 3 of us just in my very small social circle--we are approximately 30, 40 & 50 years old.
The government so far hasn't helped regular middle-class people like my friend and me (both of us unemployed). But they give AIG billions of dollars and AIG pays out hundreds of millions in bonuses to the people who ran their business into the ground.
I'm so bitter.