It’s the first day back to work following Valentine’s Day and the President’s Day holiday. For many women, today means eating the rest of the leftover candy hearts and cursing the selfishness of the single men who caused them to spend another holiday unromantically alone. But, what if the increasingly isolated situation of young women in the United States isn’t entirely the fault of self-absorbed perpetually adolescent 21st century males (as self-absorbed as they may be)? What if it’s partially the conduct of single females that’s driven up the average age of marriage and kept thousands of women apart from a spouse?

That’s the thesis of a new resource out from the Austin Institute for the Study of Family and Culture: The Economics of Sex. This short video primer posits that women offering sex “cheaply” give men little incentive to offer the commitment of marriage in exchange. Supply and demand apply to the relationships between the sexes just as much as in any other category of our market-driven world, the Austin Institute scholars explain.

As any serially single woman can tell you, more women than men want to start a serious relationship in pursuit of marriage. But if most single females are willing to offer their bodies to men with few conditions, men won’t have to look far for pleasure with no expectations.

What’s a woman to do then? Realize the power that she possesses in controlling access to her body, suggests the research team. She and her sisters might collaborate to require serious commitment from men, ideally the threshold of marriage, before giving themselves physically. Were women to place a higher value on sex, we would likely see women getting more of the commitment they desire out of a relationship and many fewer solitary Valentines.