Vulnerability in any type of relationship is a lot to ask of someone. There's also a huge difference in standards between God and humanity. Allowing someone in your mind and space, so that they can fully get to know you is a risk. Giving someone access to your thoughts, feelings, challenges, and weaknesses is a scary thing because  there is a fear of being judged. I am sure that most of us have been hurt before. However, it's hard not to go through life without being affected negatively. Building most relationships requires vulnerability and trust. Without that you have nothing. In the book of James 4:8 it says, "Draw near to God, and he will draw near to you.” So the question becomes... are you willing to be open to develop your relationship with God ? Or is that too much of a tall task?