The "that you can't routinely leave" part seems more important than the "small town" part, to me - it's a special case of the more general observation that the harder it is to leave a situation, the more likely it is for that situation to become problematic.

You might find it useful to use Second Life as a venue for practicing social skills, if you don't have RL opportunities to do so. It's not perfect - the userbase is skewed toward technophiles, with a disproportionate number of auties, so the range of conversational topics is different from RL-normal, and you can't learn to read or emit body language usefully there (though with voice chat you can practice with tone of voice at least), but it's more RL-like than most kinds of online interaction, especially in terms of meeting new people.