You are in it, you potentially don't even know you are.
It is not a single walled box but many layers, each constraining individual responces to stimuli. It is programming (conditioning) that compells you to act within confined corridors.
Some can be removed through modern psychotherapy, some or the strongest ones, triggers, compulsions, and moods can be removed through self-directed regression therapy, started by simply asking yourself, "what is the root of this behavior?" Discovering the original trauma and resolving it by telling yourself that you're not the same person you used to be (distancing), putting in safeguards to prevent it happening again (security, root), and resolving, accepting, repairing or forgiving it so that it doesn't keep triggering the compulsions. You repeat this for several months on each trigger or compulsion and eventually the prison isn't as constraining.
You can go from mostly constrained to mostly free. True freedom may ultimately not quite happen but it will feel like it's good enough relatively early in the process.
Complacency is both a gift and a curse, as you can feel good enough yet still suffer occasional problems. Pushing the process to remove those will pay back benefits.
Time and reality itself becomes arbitrary, personality becomes fluid and arbitrary, reactions become a choice, not a compulsion. Emotions are something to experience rather than be controlled by.