He's throwing a tantrum and it's not his first (in assisted living, no formal diagnosis of dementia, but everyone who works with him and deals with him a daily basis agrees he has it, except of course, the only one of my siblings who speaks to him — once every few weeks since she's out of state — but she thinks he's "fine")
The pattern is that he asks me to do something I can't or won't do because of work or other commitments, he throws a pity party ( usually involving dozens of phone calls) "I'm all alone, you made me move here, you took away my car" and I tell him I still can't help him with that particular thing (something random) and I wish he would respect my time, he decides he "can't do anything right" and flips out on me and my family, including calling my husband to complain about me (he's not allowed to have my teenager daughter's contact info because he called her up and left her a voicemail calling her a XXX-head.)
The problem is that once he has his tantrum (usually every six to eight weeks) and I don't engage, he calls my sister, the only other one of his children who speaks to him, and tells her I'm a horrible person and abusing him. My sister doesn't actually help him — she usually either complains to me that I'm not doing my job caring for him, or calls the assisted living and says I'm not doing my job caring for him. But she definitely reinforces his view that he's being victimized here.
Then a couple of weeks pass and he needs something from me or is in a better mood and he forgets about all of it, and will flat out deny that he called me names or did anything, and if I show him the emails or voicemails he gets upset all over again and says I'm trying to make him feel bad.
I need to break this pattern. It's exhausting. But at the same time, I need to set boundaries — I can't just do everything he wants me to do whenever he wants me to do it to keep the peace. I have a full time job and a family and a life and despite his insistence that he doesn't want anything to do with me, I'm still handling his banking, bills, doctors appointments, shopping etc. I just need to be able to live my life without this constant drama. How do I stop the cycle?
This will never stop, the stage has been set, time for you to give up your role in this drama filled show.
Also, your PoA paperwork specifies when your authority is legally active -- and it usually means 1 or 2 medical diagnosis of incapacity. Technically he may still be able to change his PoA so I'd get the medical diagnosis done asap.
In order to get him in for an exam you tell him a "therapeutic fib" about why he needs to go (SS or Medicare requires it in order for your benefits to continue uninterrupted) or whatever you think he'll buy. Then you go with him to the appointment with a pre-written note that you discretely hand to the staff, stating that you are his PoA and that you're concerned about X behavior and please give him a cognitive and memory test.
At this appointment make sure to bring your PoA paperwork and get it into his file.
There has been many a tale of woe on this forum about a peripheral sibling wrestling away PoA from a perfectly capable PoA because they believed the delusions of the demented elder.
Your sister is contributing to the drama as well, so let her know your plans about how you intend to handle dad. And that you're no longer playing these games SHE is participating in, they're creating bad blood and heartburn amongst you all. You're DONE now, and here's the new lay of the land.
I agree with JoAnn about getting dad a mini cognition test to see if he's going down the progressive dementia highway. Mainly because he may need to move from AL into Memory Care at some point down the road if that's the case. Speak to his PCP about it. Plus, it's always good to know why he's acting the way he is, and if it's due to dementia, then his memory and his brain is compromised and you can forgive a lot of the behaviors and chalk it off accordingly. Knowing what you're dealing with, medically, is always a good idea. If dad does have dementia, he will not be able to Showtime his way through such a cognition test......his deficiencies WILL come out and his test score will be low enough to prove it. My mother, God rest her soul, was the QUEEN of Showtiming (acting to others like she was fine when she wasn't) yet she could not pass a MoCA or SLUMS test for the life of her! :)
I know how hard all the drama is to deal with. Having a parent like this is very draining, and stepping OUT of the fracas is the best thing to do b/c it lets them know you will NOT play the game any longer. It kind of disempowers THEM from the little ploy they use to keep us emotionally tethered to them. When they don't have that trick to use against us, they start having to act like adults b/c we're forcing them to!
Best of luck.