I think that a part of intimacy is something that needs to be built, like trust, with another person.  On the other hand though, I think that with certain couples, they have a special spiritual connection.  This is not something you can build, it's something special that just is.  Sometimes people can feel the other person's presence, they can read their thoughts, they even feel a sense of electricity when touching that person.  Some people would call this finding a soul mate.  Whatever you want to call it, it definitely exists.