Zoe didn't fight to get free. She could easily have bested him, even before all the training to be the Bat. She was the warrior to Wash's jester. It was like a movie she'd caught one night when she couldn't sleep; the man was a buffoon, but he was one of the biggest damn heroes imaginable. He let the warrior woman shine, and that was one of his strengths, to accept that she was what she was. That was Wash. Truth was, that was Jesse, too.
The thought of Jesse was all that kept her from kissing the man who had been her husband. Jesse was the good she had right now, and it hurt that Wash would let her have it. No matter what Serenity's pilot said, Zoe felt like she should be punished for her happiness when Wash was suffering.
Her jaw tightened, much like the rest of her body. Too many decisions to make, too many feelings. She didn't cry. She could, and she would. But, at that moment, she didn't. She just nodded, then looked down to where he held her hands. She couldn't talk, and she hoped he wouldn't make her.
Eventually he let go, and as if on cue, the elevator door opened