Hair edges thining due to braids HELP!

Your friend has whats called traction alopecia.  It is caused by exactly what she's been doing: over use of wigs, tight braids, etc. Traction alopecia is reversible, but can become permanent if the stress on the scalp continues.  It can be reversed if she lets her edges rest a bit from the tight styles.  So advise her to wear looser styles and keep the stress off of her edges.  She can also take hair vitamins, massage her scalp in those areas, and avoid putting grease on her scalp.  Instead she should use something that allows her scalp to breathe, and absorbs easily.  I use shea butter for that, but other things that don't have mineral oil or petroleum work fine as well.  My hair came back and Im sure hers will too-- she just has to be gentle with it and give it a chance without ripping it out of iits roots whenever she styles.  HTH