Are you asking how to make a contribution, or find something meaningful to do with your life?
That seems to be what you’re saying but I’m not sure. FWIW I was also totally addicted to WoW for a few years.
Think about a change you would like to see or a way you would like to make the world better. Then, look for small, reasonable ways you can start to make that happen.
Now would be a great time to try a new hobby, too. Making things is immensely satisfying. The art department at your local college might have classes in wheel pottery, glass blowing, or woodworking. (From personal experience, wheel pottery is easy to learn, calming, engaging, and all-around awesome.)
If you can’t do that, you could take a stab at writing some fiction.
Maybe you could start a home-based business or do some volunteer work. Or you could learn writing or drawing.
A couple jellies were talking about meetup.com in another thread, and that’s a great way for shy people to get out and meet through shared interests.
At this point, though, I’d start by doing small things that get you out of the house and make you happy. Look for interesting things you can do outside, like going for a hike or to an art museum, and then go from there.