When to take over finances.

She might be having "chemo brain" -- the mental fuzziness that happens with that therapy (my FIL had it with his pancreatic cancer).

How old is your Mom? Extreme and irrational stubbornness is often one of first signs of dementia/cognitive decline. You can attempt to get her tested but not sure it will be accurate if she has chemo brain, which can go away eventually. What kind of cancer does she have? What stage?

If you have Durable PoA I don't think you need a medical diagnosis of incapacity to step in. That's what I have with my Mom and she has gradually allowed me to take over more and more of her financial management. Now I do all of it.

Ask mom if you can sit with her and have coffee and cake while she does the monthly bills. That way you can help her if she needs it. My father became extremely frustrated with the finances one day and dumped them all in my lap, as POA. We used no attorneys, no guardianship, nothing. He asked me, I had POA and I said sure.

Do you have your name on moms checks and a dual checking account at the bank? Makes life much easier, let me tell you. If you have moms banking login info, you can keep an eye on things to make sure she's not getting scammed out of large sums of money,

See about getting her into her PCP for a checkup and mini cognitive exam. Her score will help determine where she's at in the impairment scale.

Good luck to you

You cannot take over until your mother specifically requests you to with an attorney, or until she is adjudged incompetent in her own care under a court judgement, or until two doctors examining say she is incompetent to act for herself. That takes a lot. The law is loathe to take a citizen's rights from him or her without VERY GOOD REASON. If there is some way you can follow what's happening, then do so. But if this is a read danger you are going to need assessment and evaluation, and the letters to go before the court. You may even need to request guardianship if you are talking large amounts of money. Watch what you wish for. This is a difficult job and the first year for me, setting up everything with each entity (each wanting something more or different) was a nightmare. And I was ASKED to do this by a very cooperative and still relatively well brother. I would not want ever to attempt this again.

Your best bet is to set up a once a month meeting to go over mail and bills. If your Mom will allow this it makes it ever so much easier. I sure do wish you good luck, but sounds as tho eventually you will need to go for emergency temporary guardianship.