Dear @sr5367sh
Such great insights from the group. Here are a few additional thoughts for you.

PCP Deficiencies: I'm sorry that your doctor did you wrong. PCPs are fine for medical items, but I always recommend that people get a gerontologist. They have the insight from dealign with many patients with these issues. They can advise and advocate for balance on quality of life issues. Ours actually asks me at each meeting, what I need.

End of Driving Anger: My husband has been very sweet and compliant for the most part, but the were a good two years of grumpiness around the loss of driving. It wore off eventually. The doc did not blame me but my husband did anyway.

Emotion/behavior modification medications. I tend to be cautious about medication for emotional issues. But now is the time to be open to it. There are very specialized medications ( A friend told me she got a medication that specifically addresses uncontrollable crying!) I did not want to tamp down the highs that I was working so hard to create for my husband by giving him something that would address the lows or anxiety points. We got a low dose anti-anxiety drug that did away with the sadness about his father that returned again and again.

Resistance/Delusions: Regarding the very uncomfortable situation of your husband not thinking you are who you are. I have not faced that exact thing but there are other strong wrong beliefs that pop up. FWIW, I will share a couple of thoughts. One is what I saw at a memory care facility where I had to put my husband briefly. There was a lady, new resident, who arrived there and she was sure from the start that she needed to go home "today". I watched as the staff explained that her female relative was coming at 4. Then that she had called and was running late. Then that she was coming tomorrow. They did this for days and days as often as she asked. She often was by the door with her belongings, waiting. Eventually it faded and she became a resident in her own mind as well. This is to say that what seems ridiculous to assert can, indeed, be asserted and it can ultimately be compelling to the listener, or it can get them through a period of time when they believe something unshakably, but then discard that belief.
The other thought I would share is that my go-to strategy is to fill my husband's time with joyful moments so that his mind does not descend into dark thoughts. The confusion that this disease creates is disquieting at best and terrifying at worst. Your husband's thoughts about you having left may be the loss of facial recognition capabilities that another community member mentioned, but they may also be engendered by the fact that that is undoubtedly his worst fear: As he senses his capabilities decline and sees that you are is one source safety and comfort, he may mentally play out scenarios in which he would losing that. I know, because that is what I did when I was a little girl, painfully aware that my mother was the only person in the world who was my lifeline. My husband was in the hospital recently. One night he turned to me and said these whole sentences "Do your other friends ever tell you to go to another place? Do they ever ask you to do things that you do not want to do?" Understand, he normally cannot complete sentences. And the half that comes out is rarely on topic. Something, a TV program (?), just a thought(?), clearly sparked an undercurrent of fear about me being distanced from him by others.
We can reassure them, but we can't argue when they believe something. We are left with our trusty all-purpose tool, Distraction. Specifically, a stream of moments that are filled with life, love and simple things that tell him that everything is ok.

You are carrying a very difficult load. I cannot leave you without an exhortation to get help if you can afford it. There are caring lovely people out there who need the money and yet do the job for more than the money. They can create additional light in your husband's life and keep you from sinking as you carry the load for all things related to your joint life, do the detailed caregiving that increase in number of tasks first, and then increase in the time they take, and live your life.

All the best.