My sister quit her job in a huff so now she's unemployed

[yardwork]

She'd been working very long hours for low pay and she got fed up and quit. Now she has no job, no benefits, no income, no savings, and a ton of debt and financial commitments. She recently bought a house and she has four horses and other pets. She's in her mid-forties and her health is not good. Her house requires major repairs and she can't afford to do anything with it. She can't afford to buy a lawnmover or hire anyone to mow the grass.

When the mortgage comes due later this month she'll turn to our mother again, who is in her mid-70s and doesn't need this grief. I'm so mad at my sister, but I'm also worried about her mental health. She's done this kind of impulsive thing over and over again all her life, and she always turns to our parents for help - and unfortunately they've bailed her out over and over again so she's never had any reason to change.

She was in therapy a couple of years ago and that actually helped (she got a job, for one thing) but she quit that about a year ago and now she's right back where she started. She's always got some get-rich-quick scheme that never pans out and leaves her further in debt than before.

I'm not really looking for advice. I know the limits of what I can and can't do. I know better than to send her money.

Does anyone have any experience with knowing an irresponsible person like this who actually changed? I would love to hear about someone who was totally irresponsible and impulsive and actually got themselves together, got a job, sold the horses or sports car or whatever unaffordable baggage they had, paid off their debts, and started living a more responsible life? Or am I just hopelessly square?

It's not drugs or alcohol - she's sober. It's not bad influences - she has few friends (gets mad at them and ditches them) and no boyfriend or husband (can't put up with them). No kids. Just the horses.

Stories welcome. Thanks!