cesarean incision care

I need some advice ladies! My incision from childbirth just doesn't want to heal all the way. I've gone to the doctor several times for it(shortly after I had my daughter it got infected) and he tells me the same thing: saline and peroxide and use a hair dryer to make sure its dry. This has been going on for months and I've got two little spots that just wont close all the way. I am over weight, so I understand it's harder to keep the moisture out from the skin, but I'm desperate.