Please answer the following question: Given the following context:  Gloria, a downtrodden housewife, lives with her husband Antonio, mother-in-law and two sons in a small, shabby and overcrowded  apartment located by the Madrid motorway. Besides taking care of her home and family, Gloria also works as a cleaning lady to make ends meet and takes amphetamines to keep going. Her marriage to Antonio, a male chauvinist taxi driver, is on the rocks. Fifteen years earlier, in Germany, Antonio worked as a driver for Ingrid Muller, a German singer with whom he had a brief affair. His only mementos of their liaison are a signed photograph and a tape of her song Nur nicht aus Liebe Weinen which he constantly plays and which Gloria detests. Antonio's services for Ingrid involved copying letters that she had allegedly received from Hitler himself. In his taxi Antonio meets the writer Lucas and Antonio casually mentions this fact to Lucas, who suggests that they forge Hitler's diaries for big profit. There is also a book of Ingrid's memoirs written by a friend which contains letters from Hitler which Antonio helped forge. Antonio is trying to teach the art of forgery to one of his sons, as this talent will be his only inheritance. The younger son, Miguel, who is twelve, sleeps around with older men. When Gloria confronts Miguel, telling him she knows he has been sleeping with older men (including his friend's father), Miguel responds: "I'm the master of my own body." Gloria's eldest son, Toni, who is fourteen, wants to become a farmer and is saving up enough money to buy a farm by peddling heroin. The grandmother, who is addicted to soft drinks, shares the same dream of returning to her native village. Gloria's friends are her two neighbors: Cristal and Juani. Cristal is a prostitute with a heart of gold. Juani, is a bitter woman obsessed with cleanliness and vulgar ornaments, her daughter, Vanesa, has  telekinetic powers, which she uses to destroy their apartment.  answer the following question:  Whose marriage to a taxi driver is on the rocks?
A:
Gloria