Princess Anne and Andrew Parker Bowles did not marry because Anne chose to marry Captain Mark Phillips instead.
Anne and Andrew had a long-standing relationship, dating for several years before her marriage to Phillips. They were even engaged at one point, but the engagement was broken off.
The reasons for the breakup are not entirely clear, but some speculate that Anne's father, Prince Philip, disapproved of Parker Bowles. Others suggest that Anne was not ready for marriage at that time and that her relationship with Phillips was more serious.
After Anne's marriage to Phillips, Parker Bowles went on to marry Camilla Shand, who later became the Duchess of Cornwall after her marriage to Prince Charles.
The relationship between Anne, Phillips, Parker Bowles, and Camilla has been the subject of much public scrutiny and speculation. However, the ultimate reason why Anne did not marry Andrew Parker Bowles remains a matter of historical conjecture.
