"Love" -- perhaps the ability to "see people as people" (as my father once said) seems to replace "The Law" at some level. It's necessary in order for any of us to overcome involuntary vulnerability. It's necessary to have an audience that can benefit from the innovations one has made or the cultural or artistic output one has authored individually. It seems essential as a step for permanent, long-lived intimate relationships allowing co-dependency. That is not necessarily restricted just to traditional marriage.
Love -- and connectedness -- seems necessary to overcome he apparent moral contradictions or at least paradoxes in the law.