I feel like i have mastitis but haven't breast fed in last 6 years. how is this possible?

Many other causes: There are many other potential causes for duct obstruction or co ditties which may mimic mastitis. If infection is present, antibiotics are likely indicated but further work up requires a detailed history, physical examination and imaging to determine the cause of your symptoms. Aspiration, incision and drainage, or excision may be indicated based on the findings.