I had chemo Jan to April 2015, it shrunk the cancer in my lymphs. I then had radiotherapy from may to June 2015.
I was on biclutsmide but by October my PSA was accelerating fast, it only got to 4 but was down to 1 at its best, it was lower than your hubbys on diagnosis at 342 but high enough.
I then started abiraterone in Jan 2016, my PSA kept on falling until it got to 0.11 about 6 months ago. Since then it has fluctuated between 0.11 and 0.13, currently it is 0.11.
I was told averages for everything too, but I am a year past the average for abiraterone even though I was under the average for ht /chemo, swings and roundabouts.
In the two years since I started abiraterone I have run the Marathon des Sables across the Sahara twice, ran long multi day races in Spain, Iceland and more marathons than I can remember. I am 52 and I ran a bit before I was diagnosed but nowhere near as much as I have done.
In 57 days I am off to the Arctic to race 350 miles due north pulling a sledge unsupported.
I write this so that you see that anything can be possible, I never thought I would do any of the above races in my lifetime but I have.
I don't expect your husband to start running marathons but hopefully still focus on the things that you both want to do and do them. Prostate cancer will probably get me but there are no guarantees as I may be hit by a bus tomorrow, in fact any one of us may so focus on today as today is for living, what happens next month, who knows but don't waste today worrying about it, easy to say I know but it works for me. No one dies thinking I wish I worried more but many rue the days that they wasted worrying no matter how understandable that may be.