Survival instinct is high in most of our species.
Other than Islamic terrorists, of course.
I'd find a secure place to live behind easily maintainable walls near a library, plant a garden, gather canned goods, bring some cattle into the compound and start reading how-to's. And when I wasn't busy with all of that, I'd be praying that there was someone else alive and that'd we'd find each other. Maybe no cattle. They'd be a bit hard for a single woman to handle, at least one my age. So I guess I'd become a vegetarian unless I could get some chickens and find a place where fish were easy to catch.
If I got despondent, I'd probably break into a pharmacy and OD on sleeping pills.