[papa]

I like this approach (the mental RPG game).

I'd also add that you can start with small steps. For instance, with a coworker, see if they want to grab lunch one day or get some coffee during a break. Making friends sometimes takes time. You need to see if you're compatible with the person enough to be able to do stuff with them.

If you're a hacker or entrepreneur (which I'm assuming b/c you're on this site), there are plenty of meetup groups from startups. This is always a great way to find like-minded people.

If college was a great way for the OP to meet friends, consider a local extension school or community college. Consider a class in some hobby you always wanted to learn more about (photography? ceramics?).

Good luck!