I've been on a Rumi kick lately, as I love his poetry and tend to be attracted to it as certain times of my life. In this latest reading binge, I was noticing a trend in his thought. He often refers to Shams of Tabriz as his friend, and then later talks about his Friend.
Here is what I think he means. I wrote in a previous post (click here) that I believe that Shams was Rumi's Twin Soul. I don't get the sense that they were lovers -- and most scholars don't believe they were -- but I believe they shared a soul intimacy seldom found in relationships. When Shams left (or was killed), Rumi's longing for him became translated into a longing not only for Shams, his other self, but also for his divine Self.
It boils down to this, friends: our Twin Soul isn't someone who "completes us" in a romantic relationship. That implies that we are inherently incomplete. Rather, our Twin Soul acts as an impetus to becoming unified with our divine Self. We need to find our completeness within.
Want to explore this idea further? Read The Gemini Bond.