Don't want to caregive anymore.

Seems like you have done all that you can.
Nothing worse than trying to help someone that does not want help. ...and you can't force someone to accept help.
Let them know that as of _______date that you will no longer be available to help.
Let the caregiver know as well.
Let the Therapist know also.
If the caregiver is from an agency the caregiver should be reporting to the supervisor the conditions.
The Therapist is a mandated reporter of abuse and or neglect. This includes self neglect.
If you have the ability to inform your relatives doctor of the conditions you should also do that. You may not get a response or comment but once they are informed they should follow up.
Does your relative have anyone that has been designated as POA for Health? If so that person should be informed as to what is going on if they are unaware.

Don't worry about "phasing out" your assistance. Just give a date that you will no longer be able to help. If you "phase out" there will always be something that will come up that will need you attention. (funny how that happens!)

Give them an end date and then stick to it.

Everyone needs to let this patient fail.

Thank you all for the helpful ideas. I'm going to contact my family members Dr about dementia testing/physical testing to dig into things further to make sure nothing else is going on and let all Dr's know that he isn't caring for himself correctly. I'm also going to put the burden on other family to make calls and be more involved in health care. I'm only going to do things very sparingly and visit as a family member not a caregiver any longer. Thank you guys.

If there is someone else with POA they need to invoke it. They also need to come visit this person and find out what is going on. You have no POA financially or Medically you can do nothing. I would not want to be caring for anyone without POAs. If they have Dementia and end up in the hospital, you cannot be involved in their care.

Get this person to their Neurologist. That person is the best one to tell you what is going on. Write a note to the Doctor telling him what signs you see. That the person has never and will not now do what needs to be done for their care. You can no longer deal with this you need to back off. You need to know if this person can be on their own. If not, you cannot be their full-time caregiver and you have no POA to make decisions for them. If the person needs 24/7 care, you cannot set that up. Your hands are tied. If the Doctor is no help, then you need to get APS involved telling them you are done and give them the POAs info.

Good for YOU, reg. You are, by disengaging, doing, imho, the RIGHT thing!
You asked advice now on how to "phase out" after 6 years, with no one else available.

You told us in answers to other responses below that this person is COMPETENT by MD assessment.
The best way, then, to phase out is to let this person AND other family members (no matter where they live) that on _____(date) you will be stopping your services. (I am hoping you don't LIVE with this family member; ever so much more complicated if you do).

I would give a bit of time in terms of "notice" after 6 years service. The truth is that this is a shock and a massive change coming for this elder, who almost certainly is now on the path to placement (which is the correct choice).
There's already a sort of weekly caregiver in place, so access to caregiving services isn't something this senior (I am going to call her/him "Irma" because "this senior" is too long) is used to/knows about.
Start letting Irma arrange care, as she will be needing now to do this, prove competency, or move to care. Start pulling back your OWN care and advice. In the interest of transitioning Irma to the new order.

You say you don't want negative comments. I know you know that posting on social media is like Forrest Gump's box of chocolates: you never know what you're gonna get. BUT if you don't like some advice, there's another advisor right behind him/her, and you can kick to the curb what advise doesn't pertain or isn't liked. In fact we here are used to often very nasty responses to our "attempts" to help. We can't control or predict them. That's just a preface to my "power points" below.

1. Notice to Irma and to the family being done...........
2. No more advice for Irma and encourage her independence now by having her act for herself. This will help her to disengage. Unsolicited advice never works anyway.
3. Tell Irma's docs you will be leaving caregiving this situation on ___________. Tell them you've been managing/advocating far beyond what people might guess, so they should check in on her-- pill taking, hygiene, safety, appointments and etc. This can be a sort of form letter to all docs.
4. Resign any POA or legal stuff in place that needs resigning before taking leave.
5. Compile with Irma a list of phone numbers: Docs, family. APS, EMS, 911, Caregiver agency and etc. all in a nice binder big print. Consider a camera system hooked to relative's phone if they are willing so they can do wellness check long distance.
6. Consider help for YOU. 6 years! You DESERVE it. I would suggest a few appts. with a Licensed Social Worker in private counseling practice/life transitions work to help you disengage from a situation that has become enmeshing and complicated.
Honesty hurts; it's why we work so hard to avoid it. But the honest truth is that for a senior such as Irma, the trajectory (and you have seen this firsthand) is downward. Irma should be in care now. And that is likely where this will go without your intervention.

Things are going to get a good deal worse no matter what, and there will come a point you feel unable to leave, desperate and trapped. I'd advise carrying forth on what you told us you recognize must be done now for your own sake. I think it is CRUCIAL to your health and well-being. I admire your determination to do this now if your senior won't accept placement.
I know you can do this and I wish you the best. You are very attached at this point. This is very tough stuff. Again, KUDOS to you for doing this, for recognizing it must be done for the sake of BOTH of you.

I surely do hope you will update us and I so wish you the best in getting on with a great life.

Even if you are the PoA for this person, it is still extremely difficult to get an uncooperative adult to do something against their will. Yes, their Parkinson's is worsening. That is the trajectory of Parkinsons disease. It is terminal. And it often comes with dementia as well.

Although you have no power to change or force this person to do things that are good for themselves, you have all the power it takes to go on with your own life.

I'm not sure why you feel you need to "phase out assisting"? Just give notice and then leave. If this person has a PoA, then this is who will solve the problems going forward. If this person doesn't have a PoA and refuses to assign one, then you walk away and report them to APS. That's as much as you can do. Any family that criticizes this should be told to come and do the caregiving themselves.

I wish you all the best as you move onward and upward.

Sounds as if your relative has Dementia, and no longer can be reasoned with .

My mother also refused testing for dementia . She was not eating or washing or changing her clothes for me either . Mom lived alone and it was not safe . I had the County Agency of Aging come and do a needs assessment . They sent a social worker who spoke with Mom and deemed her unsafe to live alone . She needed 24/7 supervision . This was how I begun the process of having her placed in Assisted Living .

If your relative lives alone you could call the Agency of Aging , look on the county website . APS is another way .

If you live with this person , move out. Then you can call , so this person is determined not safe .

Good Luck .

Caregiving is hard and definitely not talked about enough. It sounds as if your loved one may be starting to get dementia. I know Parkinson’s and Dementia can be related. Looking back at my grandpa, we did not see the signs but he acted as if all was well too but he didn’t really take care of himself, either. I would definitely try to talk with the PCP about concerns with the progression of the Parkinson’s with possible dementia. I know it can be frustrating but your loved one probably does not even realize they aren’t doing those things like bathing, changing clothes, etc. even with you acknowledging it. My grandfather has dementia and we have to change him and bathe him ourselves and boy he did not always like it, either. When they are in that state, it is very difficult but you just have to remind yourself that they aren’t aware of what is happening or why they need to change clothes etc. If there is dementia happening with the Parkinson’s, then you may need to seek guardianship or medical POA as they are unable to make medical decisions and need help. There are facilities that can help her, however, I must warn that when my own grandfather was going into a facility, they transferred him to the hospital to be put on a regimen and allotted him out on medications. It really took a toll on his body and if I did not discharge him when I did, I fully believe they would have killed him. I know you are going through a very tough time and have some extremely difficult decisions to make regarding caregiving as it is a hard job, but I will be keeping you in my thoughts and prayers.