What Causes Fear of Intimacy?
The Merriam-Webster dictionary defines intimate as “to communicate delicately and indirectly”.

I would adjust that to “to connect indirectly from one’s deepest nature and innermost being, devoid of ego”. It comes from the purest sense of our true nature. So we would then define intimacy as a moment of being intimate. A deeply close endearing  honest relationship with others and our self.

Intimacy requires mutual sharing. It’s extremely difficult; although inspiring, to be intimate with another when they are not intimate with you. As a human being, you usually need to experience intimacy by its connection to the other person, who is open to being intimate with you. When you are truly close with another, and this is something many long to experience in a relationship, you are frozen in a moment of time with no ego what-so-ever. There is complete peace. That means there is nothing masking who you really are. There is no protection, no armor, nothing that another is blocked from seeing and experiencing in you.

This is a beautiful and miraculous event, because you  are beautiful and miraculous; due to being completely open, giving and loving.

You feel infinite love that not only touches, but nourishes the absolute core of your essence. To reach this place, is our most cherished desire.

Not so, however, when fear gets in the way. Where does the fear come from? The ego, of course. The ego doesn’t want to feel it’s death, (the intimate experience is, in fact, a temporary death of the ego) so it comes up with ways to block this experience by provoking intense fear. You can probably come up with many reasons why you might fear an intimate experience, like fear of abandonment and or betrayal however, the real cause of fear of intimacy is the ego. The ego is dependent on our attachment to our identity and in feeling separate from another, but our true nature is that we are never separate. This quote sums it up quite well:

"Our primordial fear is not of being hated. In fact, it's just the opposite. Our primordial fear is actually of being loved so completely that our experience of separation from others will dissolve entirely and we'll disappear.
The ego's survival depends on the existence of the "Other."

In fact, that's exactly what makes the "Other" so very significant. We just don't want to be alone. Ironically, our other fear of being alone is only an external manifestation of the inner fear of being "all-ONE."- Chuck Hillig

So fear of intimacy is fear of death of the ego, and fear that your identity will dissolve and become “ ONE” with another. I ask you to be willing to let that fear go, let your identity go, and share the wondrous gift of intimacy.

There is no need to continue to suffer from the illusion of  or the incorrect belief of what causes fear of intimacy.
You can have the closeness your heart has always desired without your head getting in the way.