Beyond Saturn

A young ship's Captain named Sissy lived in an interesting time. She almost starts an interstellar war that her people can't win.
Another ship's Captain named Sissy is involved in a war. After only a year there are many casualties. What frustrates her is the fact that none of them are the enemy.
She leads a small fleet of spacecraft out to explore. After several ambushes, they destroy some enemy warships, but just about get wiped out themselves.
As fleet commander, she gets a fleet of warships to stop the invasion. Her fleet is successful in destroying two thirds of the enemy empire, but again she brings back only three damaged warships.
When her ship is captured by aliens she must make the decision. Will it be life or death for her and her crew?