I think it's so odd that we base the legal binding provided by marriage on sex. Like, why is it assumed that we have to be sexual and/or romantic? Why can't it just be someone I find responsible and reliable? What does the government care the sex and romantic status of whomever I pick for that?? It's not like they're asking us how often we go on dates, have sex, or say, "I love you," to each other. We file taxes together, purchase family plans from businesses, make medical decisions when the other is incapacitated, and inherit assets. None of that is related in anyway to sex and romance. It's just so bizarre to me than the government would care at all.
Because historically the purpose of marriage was the secure economic and political alliances, and importantly produce heirs so that wealth stayed in the family. Even the idea of formally asking for the consent of the two people to be is only around 1000 years old.
Marriage first and foremost is a legal contract to bind your wealth together. The romance is just marketing.