I don't know that there's ever been any moral or legal objection to 70-year-old Aunt Bertha getting married to Old Bachelor Bert. True, procreation isn't possible (barring a Sarah-style Geriatric Pregnancy miracle) but if they are still able to unite as a husband and wife with a marital act, then more power to them.
Happy Honeymooning at Viagra Falls!
That's not even remotely related to contraception. Contraception involves the intentional impairing of one's sexual wholeness. It's taking a naturally fertile act and twisting its so it's chemically or structurally incapacitated. Old Aunt Bertha and her Old Bert aren't doing that. They're not disabling themselves.
Women are naturally infertile most of our lives, due to being pre-puberty, post-menopausal, pregnant, lactationally anovulatory, or just in the 3 infertile weeks of every month. Add that up, and at all those times intercourse cannot result in conception. That does not mean that sex at those times is "contraceptive." It isn't contra anything. It's still natural sexual union.
Gay sex isn't even a "sexual union," which means an act that "unites the sexes."
Contracepted sex, and gay sex, aren't even the marital act. That's become a mini-embarrassment in the U.K., where gay marriage campaigners have discovered that there is no act in "gay marriage" which actually matches the legal definition of consummating a marriage.
Neither is there any act possible with gay couples which matches the legal definition of adultery.
Now I suppose they'll protest because those who can't marry, can't divorce! Or because they're only "allowed" to commit adultery heterosexually!
Bizarro world.
You, as a Roman Catholic, have every right to that view, which is also echoed in some evangelical quarters. The idea to many other sincere Christians is that they are letting married Cousin Jane temporarily put herself in some semblance of the biological position of Aunt Bertha, with the consent of her husband. Good Christians do differ over this. And I do not want to offend anyone’s sincere faith in Christ.