Well, I can't comment on the Herbal Essences, since I only use it to shave, but a lot of women don't do well with coconut oil in the winter. Since it's solid at room temperature, it can definitely get crispy when exposed to even colder temps. I would try a different oil (I personally have a love affair with avocado and castor) to seal, and I'm sure others can chime in on the cowashing.