You're a programmer right? You build web apps and stuff? When you build one and launch it out into the world, do you expect everyone to drop everything and flock to your website? I hope not. You need to reach out, as uncomfortable as it might be, and engage people. It's hard work.
Now let's take your personal life. When you're at your computer most of the day, do you expect people to magically gravitate to you and be your friend? If so, you're living in a Field of Dreams. You're fooling yourself.
Try Rejection Therapy: http://www.rejectiontherapy.com. It's like a radical new form of networking. I've heard so many amazing stories of people pushing past their fear to make a rejection, and it ends up starting an amazing new friendship.
Stop being attached to outcomes. Stop being obedient to fear. Stop driving down that same road, day after day. You'll end up in the same lonely destination. Put on the 4 wheel drive and start off-roading into new territory. It's exhilarating.
People want to meet you, but you have to meet them halfway.
It's an incendiary quote (and title), and instinctively counter-intuitive, but the thrust of the article is that "no" can be very instructive and beneficial when you learn from it.
It's through adversity that people grow the most, not when life is going smoothly (although that's when the work gets done).