What do I need to be realistically looking at in terms of care?

Two things in the last month with mom:
1) She came to me insisting that the washing machine was broken and she couldn't get it to turn on. She said she pulls the dial out, and all it does is come off.
Our washing machine has a dial that you turn to set your settings, and a button that you push to turn it on. She has used this at least once a week for three years.
When I explained that you had to push the button, she was perplexed that she didn't realize that. Her old machine had a dial you pull out.

2) We had scheduled to make banana bread in the evening after dinner. She wanted to help and focused on it all day, worrying about what time we would do the ingredients, should she do some of them early, even though I assured her we would do it in a few hours, after dinner. While I was eating, she went into the kitchen and insisted on helping. She pulled out the bread pans and tried to spray them with the nonstick stuff. I explained to her we would do that in a few minutes when I was finished eating. In frustration, she brought the pan over to me and the spray can, and dumped the pan loudly next to my dinner plate, for me to spray. I said, I'll be done in a few minutes, why can't you just spray the pan yourself in the kitchen? She appeared flustered and said, "I don't know." Then she took it back in the kitchen and I had to tell her to push down the top to make it spray because she couldn't figure out how it works. She's been cooking for 50 years.

She's normally very detailed in the things she does although she relies heavily on notes. I haven't seen her forget basic things before though. This is unusual, she's normally not incompetent, even if her behaviour is sometimes odd.

She's out of it more often these days, usually when she's tired, before her nap. She's recently been sick with an infection, and taken about 4 months to recover. She was barely eating at all and was well underweight but she's been eating properly as she recovered and has started to gain it back.

As I've posted here before, she is resistant to all my suggestions regarding doctors, and to the doc's suggestions. I suggested she consider taking Omega 3's, get a vitamin D test (she rarely goes outside, ever, and refuses unless there's a doc appt), have a nutritional workup since her recent weight loss, and so on. She has the best insurance imaginable, but her answer is a stubborn "no" to even the most basic of suggestions. (She takes vitamins, she's taken them for 50 years, they're sufficient, the ins won't pay for vit D test so why bother asking). I have had some conversations quietly with the doc, but have been also walking a balance with respecting her health decisions as well. When she goes to the doctor, she is - you guessed it - "showtime" fine. Miraculously cured.

So my question is, what do I need to be realistically looking at in terms of care, home care, help with that, possible illnesses and progression, etc. She's nowhere near needing to be in a "home" and I would not go that route unless she needed nursing care that I am not equipped to provide. Right now I live with her to help but dread what may be coming and fear that I may spend the next 15 years trapped here.

I know there's a lot of advice on this site about Medicare, home care and such. We don't have any money. ANY money. (Not even life insurance, because she says Medicaid would take it anyway). I'm concerned about getting trapped into a care situation here without money for home nursing help, or having to choose a home where she would be miserable. Down the road, it's not there now, but I am concerned and would always choose to keep her at home unless the other option was medically necessary. Advice welcome, thank you.