I think some relationships are soul filled, but fall into the "For a Reason" or "For a Season" category
I have recently read Eckhert Tolle's books and although I disagree with his depersonalization of God into a vague "source," I did find his explanation of "being" so valuable. I would not have gotten through a recent disappointment without having had these books, and I feel that I now have some very useful tools to continue on a much higher quality of life.
Tolle's explanation is much like J!dub's although Tolle calls it loving from the ego rather than our being. The ego is so problematic because it seeks its own, and often what we think of love is just our ego being satisfied (soul filled). True love comes from the inner being which is not the ego. Our being is not the pain body either which each of us has from our past history to one degree or another.
I have found that in my being (who I really am) I am a completely fulfilled and very happy person, no matter what my ego says or how much my pain body has suffered. I don't have to live in those.
I would recommend reading these books for an explanation of how the realm of the soul works and how to come into the present moment, not living in the past or looking toward the future.