Thanks for your query.Based on the facts that you have posted it appears that you have what is called as Infected Bartholene Cyst
This is infection of a Bartholene Gland located near vaginal opening.
This has to be drained up properly by a general surgeon
Though it has subsided with taking antibiotics it has not not been drained completely and has recurred again.
Please consult your gynaecologist for clinical examination and get it incised and drained properly.
It will get cured within a week.