I'd wander the earth because my sanity doesn't rely on the existence of other people. If anything it would be alleviating with no danger to myself except by illness and not have to worry about being bossed around by "governments" and more powerful upper-class groups. People are the scum of the earth truthfully. There's enough of us that we can spread evil everywhere quite evenly. Enough of us where we argue what is moral and what is immoral. With just one person none of that matters anymore.
Your life would finally ACTUALLY be in your own hands. There would be no risk of having your life wasted in jail for you'd finally be accountable to nobody. of course with Nuclear Power plants being un-tended, you're going to want to be somewhere safe.
I would die either through disease or i would die old. Either way i'd die happy.
