I Have Had Myastheia Gravis For Years Now But The

i have had myastheia Gravis for years now but the last 2 yrs were no symptons so assume it is remission. do u know if someone with this disease can just be extremely tired, not muscle tired but cany wake up when asleep. i sleep at least 12 hours a nite. no one seems to now the answer. i guesss everyone is different & i have been having all kinds of tests done & so far no answer to extreme fatique.
would appreciate any info u mite have on this. Donna