I agree with Justincredible about introversion -- the Susan Cain book has some good stuff in it. But as my former sponsor says, "Sure, people are the problem. Too bad, they're the solution too."
As an introverted pretty much lifetime user, I both was solitary and isolated. Consequently, I'm socially inept -- the only people I communicated well with were bartenders. I'm having to learn basic normal sober human interpersonal skills, taking baby steps.
Do you have a sponsor? Do your AA/NA groups do fellowship? Appalling as it may seem, the whole going-out-for-coffee-with-other-people-in-recovery is actually a good way to get your feet wet in sober society.