it sounds like mirgraine i started at 4 and now iam 44 and still have them bad get it check out again they are soooo sore i no what she is going through .
Has she had a MRI? I know many accept migraine as a dx, but many times that is a symptom of something else...do ask for a MRI...look at family history as well...
I wish u all the best, and if she needs the dark and quite time, then that is most likely best for her,...u also may want to try tinted glasses to help shield her eyes from light....florescent lights have a way of making those with HA's feel worse,..so try incandescent bulbs if u can.
All the best and do post an update