What Causes Prolonged Itching And Thick, White Vaginal Discharge?

Hello for the last ten years ive had itching and thick white discharge that doesnt go away. Ive been tested for everything and get pap smears yearly.for the ten yrs my doctor said it was bv .then yeast. Recently had a pap and both bv and yeast swab came back negative. Have the symptoms. And when using the bathroom i see white clumps in the toilet. Also feel very sick and weak.please help