What of my near elderly wife and eligible for SS self? We had children before our union, but now cannot have them and wouldn’t if we could. Is our relationship not a marriage?
The natural law definition of marriage is: the lasting union of a man and a woman who agree to give and receive rights over each other for the performance of the act of generation and for the fostering of their mutual love.
Why the above definition necessarily excludes sodomite couples is that they are incapable of performing the "act of generation." (Even if all the plumbing worked properly, what they do with each other is incapable of producing progeny) An infertile heterosexual couple is fully capable of performing the "act of generation" even if they are putatively infertile.