can scabies ever not be contagious?

[marieg]

I have this terrible itchy skin rash that started on my hands but not between my fingers and soon went to my stomach and chest back and sides ,insides of my arms, behind my ears,itchy in ears and base of scalp. breasts. When i sweat it gets worse. I have bumps that i scratch and scab, they are in an irregular maybe zigzag pattern that leave scars, and my skin feels like things are crawling on me. I think I may have scabies, but I have had this for 3 months, and noone else in my family has gotten it. Has anyone ever had scabies and it wasn't contagious? What else can it be? I've been to 3 Dr's and noone seems to know, but they never test me with a scraping under microscope. Anyone Know? Thanks, Marie.