Part of the problem may also be the water where you live. If you live in an area with especially hard water, you might need to do an ACV rinse every time you wash. I do (on both counts) because it keeps the minerals from building up in my hair. That seems to have a lot to do with it being dry and not curling well.
You can check with your local municipal water supplier - city , co-op, etc. to see what your water is like.