Welcome to the forum, and welcome to the world of PSA anxiety.
I guess I am very lucky, I just take life as it comes. I have had treatment with curative intent. No test so far has indicated that it has failed. I really can't see any point in worrying about something when there is no evidence that it needs worrying about.
Well you are now living life in the new "normal". The first thing you need to know is that worrying about cancer cells won't make them go away. And if worrying isn't making you happy stop worrying, because it ain't helping.
The next thing is try and change the way you view things. In your post you have talked about what the surgeons have said, which is generally positive and a little bit of uncertainty. At the end of your post you have said "suspected positive margins" well that is your interpretation of what has been said, you could equally have said "suspected negative margins" and that would have been equally valid, as no one at the moment knows what the margins are. So always look on the bright side until you have a reason not to. You will find the new normal a lot more barable if you can reduce your worry.
So next step is get the psa result. If it is good then just go with the flow, and don't worry that the next one may be bad, because worrying won't change it.
Hopefully your OH will continue with good results for the rest of his life. If so keep posting the good news here. If things start going wrong this forum will really help you know what treatments are available and what questions to ask the medics.
Good luck think positive (unless thinking of margins, in which case think negative)