Any suggestions for the wife on how to support my husband?

From the PET it seems like he will be placed on some form of ADT - androgen deprivation therapy - to slow down any loose cells from growing.
Radiation may also be considered - over the coming months after healing or on a wait and see basis. If so, it is VERY important for your husband to maintain a vigorous schedule of exercise and weight training. Can’t emphasize this enough!!
Since you mention that you yourself work out, encourage your husband to do the same - maybe even do it together. My wife and I can usually be found together - she on her elliptical, me on my treadmill. Or run or cycle outside together, whatever you desire.
At first, my wife often chided me for exercising so much - especially when I complained of fatigue and pushed myself to get through it….she thought she was helping me. But now she’s come to see the importance of maintaining muscle tone and weight when you are on ADT and she encourages me to exercise but not kill myself doing it.
Best to you and your man - you both got this!!

One thing I haven't noticed here is that you will become more intimately involved in his genital biology and hopefully you will be ok with it. My wife, in helping me during the catheterization, had never dealt with my penis in a non-sexual way and it was a new experience. The bruising, swelling and cleaning was all new and she helped considerably. And ever since she has seen me with penis clamps, external catheters and the like and has learned to adjust to this new reality. She's a keeper.

One thing I haven't noticed here is that you will become more intimately involved in his genital biology and hopefully you will be ok with it. My wife, in helping me during the catheterization, had never dealt with my penis in a non-sexual way and it was a new experience. The bruising, swelling and cleaning was all new and she helped considerably. And ever since she has seen me with penis clamps, external catheters and the like and has learned to adjust to this new reality. She's a keeper.

That's true. You'll be a professional nurse in no time. He may not want to even look at the tube poking out for a few days - I sure didn't - so that's your department for a little while. I showered myself once I was up to it, but I didn't have the strength or flexibility to dry myself. And she largely took care of emptying the catheter for me cause I wasn't that stable on my feet.
So you'll be looking at that area in a whole new light. Try to keep your nurse's hat on while you empty the catheter or dry around it, so it doesn't put you off later.

That's true. You'll be a professional nurse in no time. He may not want to even look at the tube poking out for a few days - I sure didn't - so that's your department for a little while. I showered myself once I was up to it, but I didn't have the strength or flexibility to dry myself. And she largely took care of emptying the catheter for me cause I wasn't that stable on my feet.
So you'll be looking at that area in a whole new light. Try to keep your nurse's hat on while you empty the catheter or dry around it, so it doesn't put you off later.

Your moral support and kindness , as it will take time to get better again . Its a huge operation... but mu wife helped me in everyday . lots of frustration, but she got me walking right away , I was doing lops around the hospital. I spent a week in the hospital as I had a slight fever after operation , so they thought I may have had a slight infection, so I was kept there . Just as well , as I was around super caring nurses and my wife. Make sure he get plenty of pain control pills, IV . talk to operating dr's before he goes in. Be his eyes and ears for at least 6 months . Tell them to preserve Prostate for further testing down the road if required ( they do that here in Canada ) . Let me know if you need anything . Let us know how things go . When is the operation? , What is his PSA like , lesson size ? Did you have a PSMA PET before or just MRI like me ? God Bless ! James on Vancouver Island

I didn’t need my wife to help with any of those things. She cooked my meals for me and drove me places I needed to go to the 3 days before I could drive. She would also pick up prescriptions for me that I needed.

For me, the catheter was no big deal. It didn’t need any care for two weeks other than changing the bag, Which I almost always did myself.

What someone needs help with can vary a lot.

One of the best thing you could do for your husband is take him and help him go to a place that offers Tulsa Pro, much less problems.

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Tulsa
https://tulsaprocedure.com/find-a-tulsa-pro-center/
https://tulsaprocedure.com/
If wondering about Tulsa Pro from a science point of view, here is a basic Tulsa science overview article
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9231661/
Conclusions:
“As an alternative to conventional treatments, TULSA is safe and effective for prostate tissue ablation in men with primary PCa. There is also evidence that TULSA delivers effective relief of urinary symptoms while treating PCa in a single, low-morbidity procedure. The likelihood of freedom from additional treatment or potency preservation is associated with the planned ablation fraction.”

Tulsa or HIFU - what is the difference

Tulsa Pro uses some of the same ultrasound technology for the ablation as HIFU, but they are not alike. Tulsa Pro can handle a person with a fair amount of BPH, HIFU cannot. HIFU the lesion has limited locations that it can reach so the lesion is best if it is near the rectum, as it is done that way and only reaches a limited area in the prostate. There are other limits some places put on HIFU, and some places put limits on Tulsa too. These are limits the maker of the equipment has not put on using it, as the places doing studies almost always put more limits on who they accept. So bottom line is if you go to a place that is part of a study they may not accept you for TULSA or HIFU or Vanquish, where-as a private physician might. Meaning get multiple opinions.
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Vanquish
Something new and an alternative to Tulsa, can't speak myself to it, just to Tulsa. But it is something to read on if you are studying what to do.

Trials
https://clinicaltrials.gov/study/NCT05683691
a story on it
https://www.mnphy.com/1023-story-one--christopher-dixon
More info
https://www.francismedical.com/tag/vanquish/