Sarah, your subconscious mind is driven most by Reserve
You approach the world with your guard intact because unconsciously, and perhaps consciously, you want to maintain an element of control in your relationships with people. You tend to hold your private experiences just out of reach of others. You're not one to immediately show all your cards, to let people into who you really are until you're ready.
Unfortunately, that sometimes means you also hide things from yourself. You may find that your desire to remain guarded backfires, affecting your self-awareness. Why are you like this? It's possible that you act in this manner because of a deeply-rooted fear of being exposed, or of truly expressing yourself. To protect yourself from this fear, you act in the opposite manner — you are guarded.
There is a certain respect that comes with resistance, an unconscious understanding that the human psyche is very vulnerable. We all feel we have a lot to hide, and you are not one to be intrusive or thoughtless about how you approach sensitive topics with others. Therefore you inspire a sense of safety in others when they are around you. Your psyche is very deep, very rich, and the more you can let yourself know (both the good and the bad), the more you will be able to appreciate who you really are.
Though your unconscious mind is driven most strongly by Reserve, there is much more to who you are at your core.