Damaged hair

Hi, I am writing because I am trying to find a solution for my mothers hair loss and damage.  My mother is African American, and she had long mid back length hair that was chemically treated.  Five years ago my mother became anemic because she had a low iron.  The hair in the back of her hair gradually broke off and it changed in texture.  The hair at the top and crown stayed healthy and long.  The hair at the back broke completely to the roots and it feels like wire, its dry, coarse, and damaged.  It also has white bubbles along the hair strand (not the roots, it looks like those damage marks). 

 

 

Its been five years now, and the hair is still short brittle, dry, and it has white bubbles on the hair strands.  She has visited many dermatologist, and they have all stated that it was chemical damage, and they recommend her to go natural.  She went natural for a year and the hair was still damaged.  We constantly cut the damage off, moisturize with water based conditioners, sleep with a satin cap, and we avoid combing and brushing this area.  She alternates between protein and moisturizing conditioner.  She tried to go to the hairdresser numerous occasions, but they careless hair practices broke the hair off worse.

Can you give me some advice?  Please?