Severly damaged hair?

my hair is severly damaged. I used to bleach my hair, however over the last year I have only highlighted my hair ONCE at a high end salon. My hair is literally snapping off in the front and sides of my head.( I can pull a strand of hair and snap it off without any effort ) I use all the salon products, such as nexxus and redken. I straighten my curly hair once every other day, with a nano chi and half air dry then blow dry with a chi dryer as well. I use a heat protector and heat treatments weekly, but my hair is still just popping off everywhere. WHAT IS LEFT TO DO? I have long bangs that HAVE to be straightened or else its a scary sight.