HAIR ISSUES!

I have big time hair issues. I think it more or less started after I had Nash but seems to have gotten worse. I know hormone changes change your hair but this is pitiful. I have never really loved my hair but I haven't had these problems. My main problem is that when my hair get past my shoulders it gets unmanageable. By that I mean that it is super soft and limp. I can't even use conditioner or it would be way too oily. It seems to do okay right after I get it cut about shoulder length with layers in it for a few weeks then it is all down hill. Also it is wavy in areas, mainly right above my neck. I straighten and straighten and still most of the time have lump back there. Also as of late it has been pretty staticy. I want to just shave my head and get a wig! Okay maybe that is too drastic.
I need a fix. I haven't tried much at this point because quite frankly I don't know what to try. My friend Kat started washing her hair with a combo of baking soda and water. I read about it. It made sense. I did it and my hair was good for a couple of days and then got oily and felt soapy. I played with the combo of baking soda and water to try to make it better but have kind of given up on that.
Since I do have some curl or wave to my hair in certain areas. I have tried doing it curly by crunching it and putting product in it. That did not work well because it did good in some areas but not in others and all in all did not look very good to me.
I have thought about putting some dye in my hair. I have done "low lites" before and liked it. So that is an idea. I figured it would make my hair not as oily with dye in it.
When people cut or mess with my hair they always make comments on how I got great healthy thick hair but what's the point when you can't do anything with it. If you have any suggestions, I am all ears.