I think if there is a definite injury then you can rest/work around it/strap it up/take painkillers etc. but a general feeling of debilitation is very eroding.
More sleep, revise diet/supplements, perhaps back off training are all things I'm sure you have considered. If you are able to take a few days leave and just rest that might help. Speaking as an old fart I look forward to having an early night and if I don't get my 7hrs it starts to tell very quickly.
Do you get a good sleep? How about something like Nytol? Hope everything gets back on track.
Anyway ... as always very impressive performance despite all the problems, well done but get some rest, you young chaps are devils for burning the candle at both ends