How do I save my mother from herself - and a con man?

Long story, but I’ll try to list the events instead of describe them.
1. On 9/11, my mother had an aneurysm rupture in her head. She survived, but recovery was never 100%. Ex. social filter gone - just poof.
2. Dad died 7 yrs later. Only then do my sister + I discover how much he hid from us about her.
3. My sister lives 2000 m away. I live 45. I try to get Mom to sell the farm + move closer to me. Utter + complete failure. I discovered she never wanted children + never really loved us. (Another long story.)
4. Enter predator/“odd jobs guy.” Someone who helps her out...my age. Suddenly Mom is drinking. I get calls from her neighbors...the sheriff has been there; fighting and yelling.
5. The man’s brother gets out of jail.
6. My mom develops 8 ulcers...after taking her to 6 endoscopies- she kicks me out of her hospital room and threatens to have the guy burn my house down. She also fires our family doctor. The man claims her doctor prescribed her sleeping pills and she accidentally took too many. The doctor is my uncle. He would never do that.
7. The brother of the predator has a wife who is now in charge of my mom’s medication as a “caregiver.” Unofficially, of course.
8. I called APS; they interviewed Mom, who said she’s afraid of the guy, but as soon as he fixes the barn, he’s history. A tall tale.
9. My cousin called today, said the predator had called her to invite her to their wedding next Saturday.
10. IDK what to do to save her. My sister has a hands-off policy that seems to work for her, but, my God. This is my mother. She’s impaired. Her house has become a hovel. I worry about her pets too. Two have died under suspicious circumstances. Over the last 11 years since Dad died, the love I had for her has bled away. She’s killed it, but I still feel like my dad would want me to do something.

This man is a bad person. He has drained her finances. She has a good teacher’s retirement, but I hear she claims to have no money and she tells ppl that her daughters have abandoned her.

Sometimes I think I’m living in an alternate universe. This can’t be happening. My mom was a respected woman. It’s so awful and sad.