We've stepped up but feel lost and alone. My husband and I are in our late twenties. Last year he got a job opportunity in a different state, which happened to be quite close to his 88-year-old grandmother. The rest of the family lives across the country and she'd been on her own since her husband passed about ten years ago, so we figured it would be mutually beneficial for us to come stay with her while we looked for a place of our own, and meanwhile help her take care of things that had been neglected around the house.
Well, it turned out that things were worse than we thought. Her kids (my father-in-law and his sister) swore that she was in great health and doing really well so we wouldn't have any problems. Turns out she'd had multiple falls and broken bones, was essentially a shut-in due to incontinence issues and fears of having accidents in public, and was beginning to show signs of dementia (personality changes, flares of anger, memory lapses). We tried repeatedly to bring it up with her kids, who insisted we were wrong and that there was nothing wrong with her. We even got a note from one of her doctors suggesting that she be officially examined for signs of dementia, and my father-in-law refused to facilitate it because he was so sure she was still totally independent. (Since then we've been made official medical contacts, but it took almost a year and several medical emergencies which we were left to deal with alone before that happened.)
Since then, we've continued to live with the grandmother, taking over half of the household expenses and trying to help with home maintenance. My husband is afraid to move out because it's eminently clear that she's not competent to take care of herself anymore, and overall she seems happy to have the company. But as it becomes clearer to her that we are trying to take care of her, she's become VERY resistant and hostile. She seems constantly to be testing us while simultaneously trying to take back her independence in increasingly alarming ways - making long driving trips in bad weather (yes, she still has a license though she probably shouldn't) just to show she can; refusing to tell us items she needs from the store; even recently going to the point of lying to us about some home repairs she was undertaking so we couldn't help, then presenting us with the bill when it was all over and berating us for not intuiting that she was handling this herself and offering to take it over. She's hostile, angry, accusatory, and just generally a nightmare all around - which is both emotionally exhausting and also cements my husband's desire to take care of her, since she's worsening rapidly.
However, to her son and daughter she's all sunshine and rainbows, able to keep her mind focused just long enough for the five minute phone conversations they have with her. We feel like they've totally checked out - neither one has been to see her in over a year, even when she had a bad fall and was bedridden for six months. (We cared for her all that time - including me taking reduced hours at work to make sure she was taken care of.) They don't want to be bothered, but they hold all the cards - power of attorney, access to money, etc - and when we've tried to ask about how to deal with her worsening condition, they deny it's happening.
Basically, we are feeling frustrated and exhausted because we have all the responsibility and none of the actual authority or support we need. My husband of course can't stand the idea that his grandmother is just going to be abandoned by her family because they refuse to deal with her health problems, but he feels powerless to do anything material about the situation. As it stands, between her resistance to the idea of growing older and her children's refusal to believe us when we describe her health problems, we can't even get outside help - we have no access to her money or insurance, and so paying for out-of-home help, additional medical tests, etc would have to come out of our own pockets, which we can't possibly afford.
We don't know what to do, and feel completely at sea. We're barely getting the hang of running our own lives, and now find ourselves responsible by default for his grandmother's care. Any help or advice would be great! We really don't want to abandon this woman to her own devices, but I'm beginning to feel that soon we may not have any other choice due to the obstacles that she and her children put in our way.
Another thing you can do is petition for guardianship. It isn't cheap, but it will give you the money and legal status to do what needs to be done.
The symptoms you have mentioned are consistent with dementia. Some people go gently into old age, most go into it kicking and screaming and fighting it the whole way.
Good luck and bless you for caring.