What are Cleopatra's motives in joining Antony in the battle at sea?

This play isn't one of my specialties but I do recall the Cleopatra was involved with the politics of Antony and was certainly not afraid to join him in battle. Cleopatra was a woman of high drama even if it meant staying behind Antony’s line on her royal barge. Cleopatra was in on the strategy and the high emotions against Octavius.