I notice that most of the people in this thread talking about how they do successfully work from home talk about their wives and children.
Living alone and working alone sounds like a recipe for insanity. You've gotta have some time with other people, regardless of how much of an introvert you may be.
I've worked at home and lived alone for the past 5 years or so. I was still in college until a year and a half ago, so the lectures provided some socialization back then.
I don't think I've gone insane quite yet ;) Lots of IM and regularly making excuses to go be around people (meetup groups, running errands, working somewhere with people for a while) seems to be working for now.
Living alone and working alone sounds like a recipe for insanity. You've gotta have some time with other people, regardless of how much of an introvert you may be.