Justice Kennedy's beautiful words from the majority opinion in the OBERGEFELL v. HODGES case issued today, the two year anniversary of the Windsor ruling and the 12 year anniversary of Lawrence v. Texas:

No union is more profound than marriage, for it embodies the highest ideals of love, fidelity, devotion, sacrifice, and family. In forming a marital union, two people become something greater than once they were. As some of the petitioners in these cases demonstrate, marriage embodies a love that may endure even past death. It would misunderstand these men and women to say they disrespect the idea of marriage. Their plea is that they do respect it, respect it so deeply that they seek to find its fulfillment for themselves. Their hope is not to be condemned to live in loneliness, excluded from one of civilization’s oldest institutions. They ask for equal dignity in the eyes of the law. The Constitution grants them that right.  The judgment of the Court of Appeals for the Sixth Circuit is reversed.
It is so ordered.

All adults in Oklahoma have the ability to marry, but not all unmarried couples have the desire to marry.  Regardless, if you co-own property (bank accounts, real estate or other interests), you need to appropriately protect each other in the event of death or the incapacity of either partner.  For example, if two people live together, have a clear understanding of their housing arrangement, but the house is legally owned by only one partner, without the right documents in place, if the legal owner died, the survivor would likely have no rights to his or her home.   That uncertainty can be eliminated with simple estate planning.
http://www.tulsaworld.com/business/moneypower/retirement-estate-planning-for-unmarried-couples/article_0ed7a5da-d2ae-52ed-9d2b-dc236bd0ad46.html