You are certainly not alone! Mine was not due to Gastric Bypass - I had multiple absesses in my abdomin, and also had a fistulla (sp) due to the operation. I too had to be opened up and heal from the inside with the "help"of the wound vac.
Eventually, it stopped working, and I was healed as much as it could, and they closed me up, but not before developing multiple hernias. As the Dr stated there is a repair, however getting insurance is another story as well as finding clothes that actually hide or can fit!
Just wanted to let you know - you are NOT ALONE!