My wife's STD free. She gets regular tests. However since around puberty my pubic area has itched severely. I scratch til I bleed. What is plaguing me?

Skin problem. Check for any infestations like pubic lice or some kind of skin problem like fungal infections or eczematous eruptions get it checked with acdermatologist.
Difficult to see. I would recommend going to your local healthcare professional to have examined as it may require some medication to heal.