Hi @briankj, it's heartbreaking as we note our loved one's deterioration, sometimes bizarre behaviors, and inability to self care. I'm fortunate in that my husband still listens to me, most of the time. He remembers some rules better than others, like not to leave the house when I'm not home, but I know the day will come when he forgets that.
There is no manual, but there are resources online like Teepa Snow. You can Google her and the topic you need support with. Our HMO has a Geriatric Department. We had a two hour Zoom meeting with a Geriatrician two weeks ago and it was helpful. Half of the meeting was the doctor getting to know my spouse, the other was her going over caregiving and planning issues with me: costs of in-home care vs. memory facility, the importance for me to bring in help when I need it from agencies (for liability issues), having credit freezes in place. She wants to be involved in discussions with our dentist when my husband needs an extended dental procedure. She also advised she can help with trackers should we need them.
To @fwentz comment, I told neighbors in our area that my husband has Alzheimer's in the event he does wander, and because he did something that upset a neighbor, who told another neighbor. He watched his wife with binoculars when she was walking her dogs. She thought he was a sex pervert. I didn't realize that at the time he was blind in one eye from a cataract. Anyway, he's forgotten about the binoculars now, and that's a good thing.
The geritrician told me it's important for the caregiver to stay calm because when we get upset, the one we're taking care of feels attacked and has to fight back. I try to make that my rule, stay as calm as possible, keep unkind comments to myself, and try to engage him as much as possible.
I wish you the best.