Help Me Hair Problem?? Rough When Hair Is Wet & Tangle Feels Dry?

Okay So.. My Hair Was Long & Thin & I Started Dying It Under Black for 2 year every 3-6 months Straighten It One A Week I'm naturally Blonde & Have Thick Hair But The Last Time I Dyed It the Lady Left the Dye On Too Long.. I Got A Mild Chemical Burn Went Too The Doctors & He Checked Out My Hair & Scalp He Said My Hair Wouldn't Fall Out.. But Around Summer Time I Would Be Shedding.. & I Shed Like Crazy.. Like I Dunno If It is Normal .Shedding Started In May & Is Still Going On. But My Stylist Said My Hair Was Perfectly Fine & She Layered It But Cut It All Ugly. Then I Went Too Get It Just Get It One Length its some what pasted my shoulders.. but when i straighten My Hair It Is Rough & Hard Too Straighten It.. So I Stopped Straighten It...But When I'm In The Shower My Hair Gets Rough Tangle & Feels Extremely Dry.. I Dunno If It The Water Or What I Stopped Dying My Hair 5 Months Ago. I Still Have A Little Black In It.. But Not A lot..Don't Straighten it... ! I've Been Too Doctors Hair Salon Asking If There Is Anything Wrong With My Hair They Look At Me Stupid Like Your Fine. But I Can Run My Fingers Threw It Some times i cant It Is Mostly Always Tangled & Feels Rough.