Most of the people who go to my church are opposed to dating. All of those who do assume that dating equals sex. Pre-marital sex is what has the potential to damage future marriage relationships, even if the pre-marital sex was between the future husband and wife. Many in my church’s solution to this problem is to breathe down the neck of courting couples, which I think is a tad ridiculous.
Unless they're your parents, or hers, I'd tell them to mind their own business.
I don't know when churches became so intrusive, but more than one has. My deceased father-in-law earned my admiration when his church started asking parishioners to sign an abstinence pledge. Nearing 80, and having survived two wives, and in poor health himself, he was in no position to be anything but abstinent but he told them to shove it anyway. Not because he had anything against reserving sex for marriage, but because he found it personally invasive.