Thank you to everyone who has commented, made suggestions and offered help and encouragement. There is a lot to digest (no pun intended). It does seem that a low carb diet is the way to go and should make some improvements to my condition. I did get a low carb cook book last Christmas and cooked quite a few meals from it. I have to say they were mostly horrible and were never cooked again. I will have to find some other ways of reducing the carbs. So once again thanks to one an all and good luck with your own conditions.
If you do give it another go, and even if you don't, best of luck.
I've done some 'low carb cooking' in the past and things like fathead pizza are amazing. I also tried my own recipe for cheesecake - baked almond flour & butter for the base, a very tiny bit of high quality lemon curd on that, then full fat soft cheese on that. It was amazing and something like 6g of carbs.
If you really didn't get on with LCHF the first time you tried, the second time round you could make it easy on yourself by avoiding having to learn recipes, and going round a supermarket trying to find very simple low-carb stuff that takes no effort. Reading round this forum helps a lot, people have found quite a few readily-available foods that are an absolute treat and surprisingly low in carbs.
My personal favourite 'treats', all of which have a small amount of 'unnecessary carbs' but much less than one might expect, are:
* Mixed nuts and a tiny amount of raisins (just 3, chopped up) with double cream. A sort of high-fat, low carb muesli. Since you don't need to lose weight, you can afford to be eating high fat stuff. Unfortunately for me, I need to lose weight, and this is very addictive for me so I only have it rarely!
* Some snacks from Aldi. Their honey roast peanuts, and
https://www.diabetes.co.uk/forum/threads/surprisingly-tolerable-snacks-from-aldi.132531/
* Oppo ice cream (only tried the chocolate and hazlenut so far) e.g. from Sainsbury's
* LivLife bread e.g. from Waitrose - about a third of the carbs per 100g of a normal bread, and the slices are smaller, meaning less than 4g carbs per slice.
* Aldi's prawn cocktail, spooned into avocados. Neither of those things are things I used to like, but now they seem like a real treat.
* English mustard.
* Not pork scratchings, but very similar stuff that's much lighter / airier and doesn't break your teeth. Tesco for example have a few types, including flavoured ones. It took me a while, but now these seem like a reasonable replacement for crisps!
* Certain bags of flavoured nuts, e.g. some of the "Graze" - branded ones (especially when they are on offer)
* Aldi's dark chocolate
* Aldi's falafels (I do a lot of shopping at Aldi!).
* Humus
* Aldi's version of pepperami
* Mayonnaise, plain and e.g. garlic flavoured.
Then of course there's the normal, simple, commonly available stuff: bacon, eggs, beef, belly pork, cheese, flavoured cheeses, full fat soft cheese, pate (to go on the low carb bread!), chicken etc. Non-starchy veg like broccoli, sprouts, spinach. Mushrooms, peppers etc.
Since you don't need to lose weight, you can really enjoy replacing the carbs with fatty stuff. Belly pork, lots of butter, full fat cheese and mayonnaise etc. And when you have chicken, go for the thighs with skin on, lots of fat.
I've been making a lot of simple stuff recently. Just putting belly pork or fatty (pre-cooked) chicken in a pan, adding a couple of vegetables (sprouts, mushrooms etc), putting a lid on it, turning the meat once, maybe adding one crumbled up falafel in, then serving with mayonnaise on top or English mustard on the side.
Anyway I'm rambling, but the point is, you don't need to be a purist - do everything you can to enjoy it at the start, so you don't feel deprived. Don't get hung up on tiny amounts of sugar in things like mustard etc. It's surprising how big the list of things you like can become, and even if you don't take the purist whole-food approach, you'll be radically cutting your carbs. The purist approach can come later, if it's even needed at all, you may find it isn't.