Eurotrash by Christian Kracht

Realising he and she are the very worst kind of people, our unnamed middle-aged narrator embarks on a highly dubious road trip through Switzerland with his terminally ill and terminally drunken mother. They try unsuccessfully to give away or squander the fortune she has amassed from investing in armament industry shares. Along the journey they bicker endlessly over the past, throw handfuls of francs into a ravine and exasperate the living daylights out of their long-suffering taxi driver. The crimes of the twentieth century are never far behind, but neither is the need for more vodka.