I would guess that the chemical treated portion of your hair needs protein. Now, your virgin hair? That depends if it is fine or coarse. Fine hair probably needs protein, coarse hair probably does not need it. You are probably using protein products now because proteins are in so many products.
As for protein recipes try the Protein Loving section of this website.
3A, Protein Senitive, Low Porosity,
Wash: Suave Naturals Conds (excluding Coconut), CVSB
Rinse out/Leave In: GVP Cond. Balm, KCKT,
Style: Naturelle Gel(winter HG), KCCC (summer HG), Flaxseed gel
Love your hair: Love yourself!