If you haven't had a good workup have one ,especially your thyroid ,and heart .

Also by any chance do you snore ? Things like sleep apnea can be silently sabotaging your day every night .

I am not a licensed doctor,dont play one on tv ,and havent slept at certain hotel chain ,but saying your healthy is very generic ,proving your healthy can mean it's nothing obvious. Call me paranoid ( but before you do please know I am a card carrying member of the club nobody asks to join "=!Rare disease" , so rare I am the only person known on earth with it ,so I can be paranoid with a pedigree, I was in Emergency Services as a career before my heath went south ,and the union retired me )

So really honestly try talking to a doctor and getting labs run and check your heart , sure it could be easily explained by a trained physician as possibly depression related or it could be something that escapes easy detection like a heart arrhythmia, your normal is pretty abnormal for most people ,and I think feeling like this for more then 10 years ,you deserve a better answer ,than any of us can G,so