Hi Debbie,
It's possible that the stomach/back pain has nothing to do with Diabetes. All the more reason to get it checked out by a doctor. The instruction to reduce or eliminate the fish intake may have very valid reasons as well. Mercury poisoning is not uncommon with a high fish diet, especially with high diets of certain kinds of fish. Mercury is a heavy metal and not one the body tolerates very well so, you may want to look there for some of the doctor's reasoning.
Maybe instead of encouraging him to take better care of himself you can urge him to take better care of you - by going to the doctor and putting your mind as ease. He's your husband/partner/second part of the whole. However reluctant he may feel about
sorting out his current situation, you are part of it, too and also have a say. If he won't go for himself, will he go for you?
I'm a brittle Type 1, too so I can relate to your hubby's difficulty with control. All the more reason I give it the extra effort all the time and appreciate all the more, those moments my hubby is there to lend a hand when I crash hard or just need understanding.
Protein in the urine could indicate the start of kidney problems. Could be diabetes or diet-related. Maybe a reason the doc said to cut out fish? Personally, I like to know the reasons behind the recommendation(s) - I would call the doc's office and ask WHY fish should be removed from his diet (at the same time as I make the appointment for hubby
. Sounds like there may be other (non-diabetes)-related things going on.