I have a very similar problem, especially where you said "my body would simply run out of fuel ... I'd get this spacey, apathetic, faded feeling and have troub

I have a very similar problem, especially where you said "my body would simply run out of fuel ... I'd get this spacey, apathetic, faded feeling and have trouble focusing". Somehow a doctor figured out I was mildly hypoglycemic, basically you have to eat consistently and everything, but if you haven't eaten in too long you get that long crash where you end up just being almost exhausted for no reason. I always make sure I eat at least something for breakfast lunch and dinner and grab a small snack in the afternoon, an it helps a lot.