Shards of Honor by Lois McMaster Bujold
The novel “Shards of Honor” by Lois McMaster Bujold was published for the first time in 1986. It was also published as part of the omnibus “Cordelia’s Honor”. It’s part of the Vorkosigan saga.
Betan commander Cordelia Naismith and some members of her crew are on a planet as part of a scientific expedition that aims to assess its possibilities of being colonized. They’re attacked by a group of Barrayarans and she’s taken prisoner by Captain Aral Vorkosigan together with a fellow Betan, wounded in the attack.
Cordelia quickly realizes that the situation is more complex than she thought because there’s a power struggle on the Barrayaran spaceship and Aral was abandoned on the planet. Despite their deep cultural differences, she and Aral find themselves working together because it’s the only way for both of them to survive.