As a friendless adult, the stage when you're in school is crucial in making friends. You're there a lot of times with the same people every week so you ought to make the most of socializing there. When adulthood comes, it becomes a bit harder. Why?
I think it's because adults have a lot of responsibilities, and have already got their circle of friends figured out. Their friends' birthdays, marriages, kids all in their busy schedules not to mention work, loved ones' occasions too. Sure they're 'open' to having more friends but you're not in the priority list.
If you're friendless as an adult and want to make friends, all I can give as advice to you is to frequent places where you're comfortable. If you like to unwind by drinking, frequent smaller bars (but don't get fucking drunk obviously). If you like books, go to libraries, church, any social events you agree to. Find local people online and go to those meetups. Talk to people about trending news and soykaf (not political or controversial stuff). Frequenting bars worked for me for a while. Almost got a genuine friend out of the bartender before I fell into crippling depression and cut myself off from any social contact entirely.
As for approaching women, it's kind of the same thing, but a bit trickier. Personally, I always say on /r9k/ for similar questions that one should work on oneself first. If you think you could lose a little weight first, do it. If you think you need more self-confidence, work on it, etc. The reason I say this is because approaching women is, like I said, a little tricky. It's just like making friends with them, but you have to be prepared to be rejected and be fine with it.. and it will happen a lot. I say this from experience. I'm admittedly your average *chan goer, spilling spaghetti and being typically pathetic with women during my younger years, evaluated myself a lot (and still am), and recently got an attractive girl to rest her head on my shoulder (as practice).
After all that wall of text, I still don't think I'm an authority when it comes to friends, and I don't think anyone does too. I'm just offering you my genuine advice from anon to anon, where those steps have worked for me before some stuff happened.
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