How do i save my hair from EXTREME breakage?

I'm biracial, but i've got african american hair. In the middle of my head, there's like REALLY REALLY REALLY bad breakage, my hairs short in the middle/back area like as if i was a boy. That makes it hard to do alot of things like straighten my hair and even pull it up into a ponytail. Besides that my hair breaks all the time and i always have little pieces of it on my shirt after i'm done combing it. I've tried all the things from dove, pantene, suave, (granted those arent really good products) but i even have used specific things i've been told about from sallies Still though, my hair won't grow, or stop breaking. Its like when i put oil in it, the oil is just lingering on my scalp, rather then helping my hair get better :( I've stopped relaxing it, dying it, pretty much i let it be. But i wanted to know if there was anything better i could do to save it... thanks for any answers