I read this memoir in my childhood in the 80’s or 90’s.  May have been paperback, may have been hardcover, and it was not a new book when I read it.  Was possibly only published in Australia or Europe (my friend got it from her Auntie in Western Australia, but they are of British heritage so it could’ve been from there, too).

Woman in the mid 20th century decides to drive her Defender across Europe and Africa, working as a nurse along the way. She settles down but eventually gets restless and decides to keep going, driving her Defender back (or maybe it was around the rest of the world?).