Probably worth noting the amazing Jane Austen and her works. The prototypical RomComs.
It was common for officers at sea in the Royal Navy to have a wife at home die in childbirth. Then he would complete a career, up to Admiral, age 50ish, and seek a new wife and children.
Times were hard. Parents would agree to a marriage of their 13 year old daughter to such an officer nearing retirement. He agreed to keep his hands off of her for X years, while she (and they, the parents) receive some portion of his salary sent home for her upkeep. This was very common and normal and ensured the survival of her family, and, indeed, her prominence as the most powerful woman of her town after the admiral’s death.
Point being . . . there is lots of semi respectable precedent.
I'm pretty familiar with Jane Austen, and none of the plots of her books include this storyline about marrying 13 year olds.
No.