Is there anything that can cause constant fatigue, mental fogginess, depression and numbness?

See Below: What you describe could be symptoms of mental condition, physical condition or both.I would recommend going to your primary care doctor and have a full check up. If everything is fine, or if there's a physical ailment, i would still recommend contacting mental health provider to help you cope with your symptoms.

Cause: Multiple causes including medical, drugs, depression, anxiety, sleep apnea.