This one's definitely for the construction kit but I thought I'd put the idea out there as I think it'd be an elegant way of disabling the (intolerable!) romances, a kind of reverse Amulet of Mara

There's a very easy and reasonable method of blocking off the romances in the vanilla game called not taking those flirt choices.

and Since when did wedding rings stop Flirting?

I get this point of view but it's not as easy to ignore with the full dialogue mod, I'm gonna see those teeth grindingly bad lines no matter what