Hello,
Constant tiredness and fatigue can be due to anemia,chronic fatigue syndrome,hypothyroidism, disorders of the hypothalamus,psychiatric disorders like depression and sleep-related breathing disorders.
In your case it can be due to insomnia or due to anemia. Get your hemoglobin levels checked and eat healthy nutritious iron rich diet.
It is very difficult to precisely confirm a diagnosis without examination and investigations and the answer is based on the medical information provided. For exact diagnosis, you are requested to consult your doctor. I sincerely hope that helps. Take care and please do keep me posted on how you are doing.
Have you had an iron test lately ? Also your b12 might be low...that will make you tired as well. I don't sleep well either so I know what your going thru. Some people like a glass of wine ...they say it helps....I haven't tried that one.