Caregiver suggestions and coping mechanisms help

I am looking for some help with my situation. I'm caring for my wife who is nearing a second year with MS (Multiple Sclerosis).

I'm hoping to get some advice on how to move forward and keep myself in some realm of healthy and normal - whatever that means.

We have not had good luck so far at finding the right treatment for her condition but just started a new one and hope it will have some actual benefit.  She has multiple new lesions and they are affecting emotion, balance and several other areas of the brain. The doctor can literally point them out on the MRI and tell us how they affect her mind and body.

The reason I'm asking for help is that I'm feeling stressed at every level and need to understand what to let go and what to address.  Knowing her brain isn't working right isn't enough to help us cope and operate our lives.

If you have the patience, I will detail some of the issues. It's not meant to be a case against my wife (I really do love her with all my heart), but
should help me to clarify my concerns.

Some background: My wife just lost her dad (huge emotional and otherwise trama). I did my best to assist her emotionally but it
just doesn't matter in the final analysis because it's her loss and she'll deal with it however she chooses. I lost my mother last year and that was really tough for me. One thing I learned with my mother who had Alzheimers was that you don't argue with someone who is losing their mind...it puts them in a loop and agitates them. I'm not sure if it is the same with MS so that's what I'm trying to understand.  When to act and address and when to retreat and tolerate as best you can.

1. Control issues: My wife has latched onto the Wahls protocol and has made it her life's mission to follow the diet and perceived benefits to
the exclusion of all joy in life and food. She has begun trying to control my relationship with food. I am the one who introduced her to clean
eating and totally support her weight loss of over 100 pounds. I'm not a dummy - she feels a total loss of control in her life (can't drive, has
trouble working, trouble with her mind and body, etc.). I am doing everything I can to help her stay involved in her work and creative life at great cost to my work and creative life.

Should I just ignore when she attempts to control me? What has proved helpful for you and your spouse with MS when they try to impose their
systems/controls onto you?

2. Emotional abuse: My wife typically is very nice and warm to me in the morning and by the time she's tired in the evening she turns verbally mean. I'm starting to dread sundown because nitpicking and fighting will happen unless I emotionally retreat.

Is sundowning an issue with MS that isn't found in the literature? Any suggestions on how I can cope with this in the evenings? Should I leave a couple of evenings a week and go elsewhere (that seems selfish/avoidance).

3. "I've always been this way": It's become a trope in the last many months that she will tell me she has always been "spacy" and "ditzy" and
otherwise not in her right mind. Although she is correct that she has traits that mirror her behavior, they are objectively more severe and sometimes pose a risk to her. She takes chances she wouldn't normally take and doesn't operate at all like she did when healthy.

Do I just let this one go? I'm guessing so...but draw the line when it seems she might be endangering someone. Any thoughts so I don't make any
significant mistakes with her or others?

4. Stress: I know stress is bad for MS. She has had a lot of it recently and it's not getting any better. She has developed new lesions and has had seizures right after times of exceptional stress. We are entering a new territory here with our relationship issues, death of her father and an upcoming commitment which will keep her on edge for many weeks.

There is no avoiding this one so any advice on coping mechanisms would be appreciated.

Thank you for any and all help you can provide.  I wish you all health and happiness.