I'm a newbie with the same problem you're having. I added a Porosity Control Conditioner rinse in between my moisturizing shampoo and DC, when I washed my hair on Monday. I also used Sunsilk Hydra TLC 24/7 creme. Both these products are new to me. I don't know which one did it, but, my hair feels like silk. Hard to believe it's my hair. LOL I've had no problems with brittle hair since.
Porosity Control helps your hair keep the moisture in. You can get it at Sallys or another BSS. Sallys had a 1.6oz trial size bottle for 1.89. Sunsilk Hydra TLC 24/7 creme can be found at any drug store, Wal*Mart or Target. Target here had it on sale this week for $2.99 in a 7oz bottle.