No conventional Doctor was able to figure this out. I went to many. I ended up with an Integrative Doc and they ran lots of bloodwork. I too had mono in High School. My GP says I’m ‘depressed’ and that’s why I’m like this. I have a response to that comment but will refrain from posting it.

Long Covid can reactivate EBV.

EBV NUCLEAR AG EBNA AB IGG
and
EBV VIRAL CAPSID AG VCA AB IGG
To detect a reactivation.

I can’t seem to get my numbers below 600.
“Rollercoaster of nonstop symptomatic hell” accurately describes it. I feel ridiculously bad today.
I hope you find your answers. I’m here if you have other questions.
I wish I could tell you when it will resolve. Good luck my friend.