What she hates the most, about all of this, is that Wash got hurt. Doesn't matter how minor, not really. No one'd kept him in the loop. If she had, maybe, he'd have had his side arm. Inches over and she'd be burying her husband, too.
Seeing Tracy has brought up too many memories, too many reminders of how far she'd go. And what she's having a damn hard time with now, is reconciling the fact that this man she'd promised to carry in battle, a man she'd literally killed for, turned on her and the captain the way he did. Held her crew hostage. Threatened the life of her husband. Her shot alone was likely enough to kill him, Mal's sped things up. She'd do it again. Always, she would do it again which hurt. Made something in her uneasy.
Eventually, when she realizes the boat must have broken atmo, she makes her way to the bridge, standing in the doorway, looking at her husband in that beat up looking sweater. She has no clue where he even got it.