My mom told me to get out. I'm leaving this weekend. Any advice on future care for her?

First you talk to the police department. Tell the cops that your mother has kicked you out of her house and you have left. Let them know that she has dementia and is an at-risk, vulnerable adult who is now alone since you are no longer providing caregiving to her. They will call APS.
While you still have POA, you could have her taken to the hospital involuntarily against her will. Call an ambulance and tell the paramedics that she will be a hostile transfer but that she's behaving violently and threatening you and herself. That will get her into the ER. You follow them there.
When she arrives tell them that you need a 'Social Admit' for her because it is unsafe for her to be alone. Let them know that you are not staying at her house anymore and that you refuse to continue providing care to her.
The ER will send a social worker down to talk to you. Do not let them talk you into discharging your mother into your care because they will try to. They will promise all kinds of resources and a limitless supply of homecare assistance. It's total BS and they aren't going to do anything. Refuse to take her.
She will then be admitted into the hospital and they will keep her there until a bed in a suitable care facility becomes available.
Or they will determine that she is safe to discharge (I've seen this happen when God knows it should not have)and they will send her home.
Either way you are covered because you didn't just abandon her and walk away. Get that POA out of your name though.

I know somebody in similar situation not so long ago, she had to leave too, but, as it turned out Mom was beginning to progress rapidly with her disease, experienced few of those strange behaviours, which, while not to excuse it, went away and she hardly remembered what happened.
They spent several last months of Mom‘s life living together in relative harmony.
I am not saying this is right for you, it is just sad what we as caregivers have to go thru.

I am assuming in my answer to you that Mom is not currently diagnosed with dementia. Were she to be so, you as POA would be/could be accused of abandonment.
That a given, that Mom is still safe today on her own or not diagnosed unsafe, I am glad you are leaving and saving yourself for your own life. Who has contact with your Mom after you leave? They should call APS if they consider her at risk and report her as a senior at risk, or call the ambulance to transport her to hospital. When you receive the call from APS or hospital do let them know that you are physically and mentally incapable of taking care of your Mom, that you have tried and can't do it.
The State will take over and appoint a conservator who will place Mom in care and manage her finances. You will not have a "say" at that time, and will be able to do nothing for visit her, which may be best for you both.
Best out to you.

I agree, contact the lawyer, and call APS. When you call APS you will need to talk to them very specifically about why you left and you will need to give them specifics as to why she can not take of her self. You might want to speak to a counselor about leaving and you might want to spend some time with them establishing that you are leaving for good. Leaving and getting out isn't the hard part. Holding that boundary is.

The lawyer that drew up the papers for the POA probably should be notified.
If there is an alternate that could be POA it would be good to notify them. That is if mom is still competent. A brief discussion with the lawyer will determine that. If no one else can be listed as POA it is possible that she will need a Guardian. If no one wants that role, and it is not an easy one. The Court will appoint one. The lawyer can rush this if it is a matter of keeping mom protected.

You can call Adult Protective Services (APS) in your area.

Do you have POA? You might need to somehow keep her safe until a new guardian is chosen. APS can answer this question.

Good luck to you.