I am a girl, virgin, and a psychology student. so let me answer this from a psychological and neuro-scientific perspective:

There is actual research on this-

which each time a woman changes sexual partner, her ability to release the bonding hormone (Oxytocin) diminishes. The same thing is NOT true for men.

Now why do we give a damm about oxytocin?

Because the bonding hormone is necessary and vital for entering and staying in a monogamous LTR/marriage.

There is research on that as well-women with lower levels of oxytocin are more likely to divorce.

Keep in mind that oxytocin is also vital for being a good mother.

Thanks for reading my scientific blah blah blah.