"don't try to find a girl who will make you happy" - that's major overthinking. "Should I also make kids ASAP and care about them" - yeah pretty much. Now if you have a super full life with lots of extended family, friends, dream jobs, hobbies, community involvement - sure, you might be happy without girl and kids. But most people need happiness right at home, instead of constantly having to chase it around, especially as they get past college age.