Best hair? / RANT pls help if you have/work with wavy/curly hair

I recently got a diffuser but when I use it my hair is straighter and frizzier and grosser than when I plop dry it!! It's very dry even though I use shea moisture deep conditioner every time I co-wash my hair. I've gone curly girl (no sulfates silicones parabens) and I think I've tried every moisturizing hair product ever. I can't find a styler that gives some hold but doesn't weigh down my hair and make it look shiny and super defined like ramen noodles. I'm at my wits end and I just made an appointment with a hairdresser that my friends mom (who has frizzier wavy hair) likes JUST so I can ask her how to control my hair. I'm just so annoyed by it. I deep condition but as soon as I rinse with cold water my hair feels dry and tangles. AAAAAGGGGGHHHHHH pls help me if u can