Seeing a cactus in your dream suggests that you are feeling invaded. Your space is being crowded and you feel like you are being suffocated.  The prickly spines of a cactus represent your wish to establish a boundary for your personal space and privacy. Perhaps you have found yourself in a sticky situation. Alternatively, a cactus may be symbolic of your need to defend yourself in some way.  Seeing a cactus in your dream can also signify your need to adapt to your existing circumstances instead of trying to change them.