Rebels of the Red Planet by Charles L. Fontenay

From the time she saw Dark Kensington die until Nuwell's arrival at the Chateau Nectaris a day later, Maya remained in her room, half in shock, half in an agony of sorrow and remorse.

She was so exhausted by her ordeal that she did sleep, but it was fitfully and without genuine rest. She had her meals sent up to her room, and ate automatically, not tasting the food.