I disagree. No christian churches should recognize unions of sodomites.
Retaining marriage as a Christian institution means not being required to recognize unions of sodomites. Christians should be able to live out their spiritual faith without secular governments corrupting the meaning of marriage. Governments should proceed with the level of tolerance, which allows Christians to be in a country, but not necessarily of the country in every way. Governments can then use their penchants for elegant writings to describe whatever other unions they want between humans. Just leave stark contrast to exist.