JOIN A CLUB! Smaller settings with people that show up voluntarily (in other words, for fun) provide for a great opportunity to meet people. A handful of people who go to clubs are quite outgoing people that would love to have more friends.
Pssh. Take up guitar, find a favorite player (I recommend John Pizzarelli and Pat Metheny to check out), and depending on what grade you're in, hire a private instructor to teach you, audition into your school's jazz band after you've learned some chords, and meet new people. School music programs are great social mediums. Perhaps you might giving choir a try. Sounds lame, but everyone I know who has ever done choir are really close with their choir buddies.
I totally understand that meeting new people is easier said than done. I'm not an open person either. To this day, 50%+ of the time I don't converse much when in a group setting. So what do I do? I find a hobby, an interest, and/or a passion. Focusing on that removes the focus on "woe is me, I don't connect with anyone." I've gone through the same thing, so I have the authority to say that that is the best way to describe it: "Woe is me."
No better time than the present. If you keep telling yourself now, "I have too many things going on," you will continue to tell that to yourself twenty years from now, then you will regret not having learned in your youth.
I keep telling myself I'm way to busy to be doing music. But, somehow, it all works out.
Used to play 30% avant garde in my improv, but then I decided I needed to go back and learn the rules before I could break them. At the moment, I'm trying to master straight-ahead jazz (Standards/Bebop). My goal as a player is to develop into a cross between John Coltrane's solo ideas and Branford Marsalis' tone.