Fluid Buildup Drainage/Aspiration after Bilateral Mastectomy

I had a seroma in my armpit after a wide excision and node clearance ( my cancer came back in my axilla) that delayed my chemo by 8 weeks. The bloody thing just kept going. I had it drained 12 times-- no sign of infection but there was a pocket of fluid that delivered over a litre a week. 
It eventually started to septate--strings appeared in the pocket then the sides started to stick together. Then it stopped. It will stop. Eventually.