Hi krispy, I am no expert but my guess would be that your hair has been building up too much protein (I believe it's in both the SM and BRHG). My hair did the same thing - got totally dry and brittle. Since nothing else in your routine has changed, that might be the problem. All the stuff in my signature is free of protein. You might want to just give your hair a break from it for a while and try again once it feels healthy enough. That's what I'm going to do. I can't bring myself to throw away my brand new bottles of SM conditioner and LALSG (I didn't know that was my problem! Now I know
It could also be that you are sensitive to the oils in the SM... Good luck!