Of course it happens both ways, but it is more common for females to move from the family home, to the boyfriend’s home, to the next boyfriend’s home, to the next boyfriend’s home.
One of the depressing things for a man to realize as he reaches into his 20s and late 20s, and his 30s, is to realize that the “girls” that he is running into, have never lived on their own, they were never the single girl of the Mary Tyler Moore sitcom, living on their own and dating, instead they merely move from one man’s apartment, into the next one, their love always involves a residence.
Sorry you’ve met such lousy girls. In my single days in NYC, all of my girlfriends (including myself) lived in walkups, held down jobs and paid for the apartment rent themselves. There were rental agencies that were solely devoted to putting women together as roommates. We even had rooming houses for women and one famous hotel: The Barbizon.
In my tiny pied a terre in NYC, there are several young women living alone. Not unusual at all.