Recurring abcesses, for a few years now. very painful. blood tests normal. what could it be?

Recurrent abscess: There are couple of reasons for recurrent skin infection, the common causes include: carrier of bacterial called Strep, Diabetes, Inflammatory bowel disease. The less common causes are Primary immune deficiencies that your doctor can test for them.

Staphlococcal infect: may have staph colonization of skin or MRSA; needs cultures done to confirm diagnosis

Abscesses: I am assuming you are getting them in several areas or is it just one area. If just one area then it needs to be CORRECTLY surgically treated. This means draining the abscess and once is scars down, removing the scarred area and walls of the cyst until ALL of it has been removed. If in multiple area, concern for immune system problem which requires medical evaluation. Hope this helps. Dr R