For reasons which are obvious ... and boring ... I performed, in my Anglican days, very few "blessings" of Marriages.
But I did conduct one such event. Having satisfied myself that the couple had aready lawfully contracted the state of Matrimony, I allowed them to devise their own 'vows' for the subsequent 'Blessing' ... subject to my own scrutiny and appoval. (This devisal seemed to matter to them a great deal; I think they saw it as agreeably personal and individual ... unlike the official, formal, goings-on.)
When I saw their draft, I made clear that there was one element that I could not sanction, because it contradicted the Church's teaching on Marriage.
They were surprised when I revealed which piece of wording I deemed unacceptable.
It was the bit where they wished to speak about their love and their marriage being "eternal".
I explained that, in the Church's doctrine, their marriage would terminate when one (or both of them) died.
Matter here for thought ...