Why are you having dreams where you see this horse woman and every day that you see her you can ask to turn into anything you want?

This is a wish-fulfillment dream. The subconscious mind creates a lovely, magical story in which the dreamer can have or be anything desired, all in the safety of sleep. It is not clear whether the "horse woman" is a woman riding a horse or the mythical centaur in female form, such as popularized in Disney's "Fantasia." In either case, the horse woman image suggests a fairy tale setting in which all dreams can magically come true.