There’s lots of argument these days, thanks to the marriage equality movement about what is a marriage. I think the religious guys have it wrong. (now there’s a surprise!) I think the legal portion of oh, now, what am I going to call it, marriage, is about protection for the family. That should be accomplished by a civil union. Everyone should have access to a civil union. No separate but equal, just a civil protection of your rights as a couple and a family. And then there should be a celebration of the marriage (if one chooses). The wedding ceremony celebrates the spiritual or sacred union, in my lexicon. This is true for all marriages.
Tip: Find a religious institution or a priest, minister, celebrant or officiant, who will help you create a ceremony that celebrates your particular Love and the marriage that will be the outgrowth of it. Once you’ve designed the ceremony, make sure the celebrant announces that you are married. Have that announcement already incorporated into your marriage covenant and ask your celebrant to sign it. Then: Hang it on the wall and live into the marriage that is worthy of your great love!