MARKET RASEN, England — Karl Bushby has spent 28 years walking home, but as he approaches the finish Monday, it’s not clear he's ready for the audacious journey to end. Pushing a cart loaded with camping gear up a busy country road in northern England about 30 miles (50 kilometers) from the finish line, Bushby was uncertain of the future, anxious about the prospect of living in his mom’s basement and facing an identity crisis. “My purpose and reason for living is about to end,” he said. “It’s going to be difficult … trying to blend back into a society that you just don’t know anymore.” Bushby, 57, was just shy of 30 when he entered the unknown at the tip of South America on Nov. 1, 1998. Since then, he has walked 31,000 miles (50,000 kilometers) across four continents, navigated shifting ice over the Bering Strait and swam — a generous description of his technique — across the Caspian Sea and English Channel. He has battled almost every type of element and terrain imaginable through 30 foreign countries to get back to where he started half a lifetime ago. Swampy j