While you're trying to solve the problem from the inside, may I advise you to check out the Long Hair Care forum (google it). Women on this site have in general very dry hair, and they're always on the lookout for stuff that works. Be careful that some products leave greasy residues, and those won't work for your hair if you have straight-ish thin hair. I use some keratin products that people recommended there, and the co-washing (shampoo + conditioner at the same time) tricks, and use good brushes that help prevent breakage, etc. Can't remember the name as I put the products in different bottles, but check it out for yourself. I live in the UK and found a few of the products here.
At least you might learn more about what to do to conserve your hair while it grows back.