April 25,1973. Entertainer Dean Martin, 55, married his girlfriend of two years, Cathy Hawn, 25, in a small ceremony at his Hollywood home. Frank Sinatra was his best man. It was the third marriage for Martin and Miss Hawn's second marriage. Her 6-year old daughter, Sasha, was the flower girl. The bride wore a peach champagne French chiffon satin bias-cut gown with a high draped neck and a long train.