I don't know what to say. I ate similar to what you described for a very long time (15 years) and thought that was going be it forever. Early on I thought it was an amazing discovery, and this was a long time before paleo eating was popular. But over time it really was not a good way for me to go.
I did a ton of Liver Flushes and then my whole metabolism started to change drastically. Potatoes, starch, rice and all those things keep me energetic and fit now. Anything more than a tiny amount of meat, which I still need, makes me bloated and fat and gives me dark circles under my eyes.
About once every 10 days or 2 weeks I eat a large protein and fat meal like a fatty rib steak, and it helps to keep me balanced. But if i continue that for the next day I'll put on a ton of weight literally overnight.
I can't say I know the exact reason for this but my guess is that my liver was unable to store or make glyocgen when it was filled with stones. When that stuff started to come out then it could do its job more normally. It might also have to do with the fact that my absorption got a lot more efficient after doing a low carb diet for many years and detoxing my small intestine. Those are just my best guesses but it could be anything. Also I've been working for years and years on dumping metals through saunas and intestine detox. My body temp stays near 98.6 without the protein whereas before the metal detox I needed the protein to keep it high.
Without either sugars or starch my energy levels would plummet and there's no way as a cfs person that I'd willingly let my energy levels go down a lot except if it was for a short term cleanse. The best I can do is just eat as many vegetables as I can, which will be less than recommended and see if the supplements will help. Maybe I'm really low on some nutrient that will change things again.
Not only has my energy level gone way up but for the first time in god knows how long I'm starting to get muscle definition back. I guess it will be interesting to see what the NB person says.