What is wrong with my hair and how do I manage it?

Ever since puberty, my hair went from smooth and wavy to wavy with massive frizz. It looks like some kind of wave/afro hybrid. I really don't know what to do about it.

I've been trying to treat my hair as curly hair lately and keep it hydrated, but nothing seems to work. Those frizzy bits just stay up, even if I slather my hair in coconut oil. They'll just grow in whatever direction they please. I can't keep rebonding (permanently straightening) my hair as it's now damaged and insanely dry and the treated parts of my hair (not pictured) need to be chopped off now. I don't want to have to iron my hair daily either as it's not good for it.

At the moment, I wear my hair down at home, but have no choice but to tie it up tight while it's still damp and slather the top in hair gel to remove the frizz and prevent the waves from setting in. I then straighten the pony (not regrown parts of hair) and put on a head band to keep it looking neat. I am SICK and tired of how much work it is just to make my hair look presentable and how uncomfortable it is having to have my hair up so tight on an almost daily basis.

So my question is- do any of you have hair like mine? My hair will be really short once I cut off the dead/treated parts and I'm worried a nice cut, curl cream, and hair gel still won't work to make it look presentable. What do you think?

P.S. Those pictures don't do justice for just how thick my hair strands are. And all I can feel running my hand over my hair is the frizz.