What's your opinion on the attitudes of young men vs. young women?

Being a college student, I notice some interesting dynamics among guys and girls. Girls seem to need a guy to complete them. If they drunkenly hook up with someone over the weekend, they find themselves hoping the guy will text them or follow up, or at least demonstrate some shred of giving a crap. They want someone fairly steady, if not an actual boyfriend, but someone they can keep going back to even just to hook up. They want to feel somewhat special. I’m not saying I’ve never been guilty of this, but I try to provide a voice of reason to my female friends. I tell them, guys just don’t give a shit. They won’t think about you twice. Do you think this is correct? Why do guys seem to never feel any connection when girls do?