Dreams filled with chaotic scenarios and unexpected events, like the one you described, often reflect feelings of anxiety, uncertainty, or a sense of being overwhelmed in your waking life. The presence of a gang and the need to escape could symbolize feelings of being threatened or pressured by external circumstances, possibly related to school, social situations, or personal challenges.

The journey to your grandparents' house might represent a desire for safety, comfort, or a return to simpler times—places or people you associate with security. The impossibility of traveling across the ocean suggests that you might be feeling trapped or constrained in your current situation, unable to escape your worries.

Meeting the supposed secretary of defense and breaking into a house could symbolize a desire to challenge authority or societal norms, reflecting perhaps a rebellious streak or a quest for adventure in your life. The bizarre birthday party tradition of the horse running rampant might represent the unpredictability of life or unexpected consequences of your actions.

Overall, this dream may be urging you to confront your fears, seek comfort in familiar places, and navigate through the chaos you might be experiencing. Consider reflecting on areas in your life where you feel threatened or out of control, and think about how you can address those feelings constructively.