If Antony love Cleopatra why did he consent to marry Octavia?

Anthony could not, under Roman law, marry Cleopatra. According to Wikipedia, his wives were: * First marriage to Cornelia Cinnilla, from 83 BC until her death in childbirth in 69 or 68 BC * Second marriage to Pompeia, from 67 BC until he divorced her around 61 BC * Third marriage to Calpurnia Pisonis, from 59 BC until Caesar's death