To dream about your stepmother in your dream suggests that you are seeking to develop your own individuality. You want comfort and guidance, but you may have to create that for yourself.
If you don’t have a stepmother in real life, this dream may be a signal that you are following the wrong path. Or, you may be having issues of abandonment or disagreement with your real mother.... My Dream Interpretation
If you dream of being a stepmother or stepfather, then this dream is about your feelings of not fitting in, being seen as an intruder, or an unwelcome interloper.
If you are a dream of dealing with a stepmother or stepfather, consider your role, and feelings toward her/him. This dream is revealing your feelings and attitudes about unwelcome and disruptive energy at home. Alternatively, this dream can also signify a desire for more mother/father love in your life.... Strangest Dream Explanations