Unfortunately for the rest of the characters, Mark and Alec take up most of the spotlight in The Kill Order. This is mostly because Trina, Lana, and Deedee have a bad habit of being held hostage somewhere.
But from what we get from Trina, we can tell she's a tough cookie. In fact, she seems much tougher than her guy-pal, Mark. Unlike Mark, she likes to rush toward the action—which eventually transforms him into a tough(er) cookie too. Phrases like, "We need to get up there, see what's going on—see if we can help" often come from Trina (8.46). Or even, "'What?' Trina asked him. 'You don't think we womenfolk can handle ourselves?'" (22.41).
We even learn that when the sun-flares hit, Trina was the one who snapped Mark out of his scaredy-cat persona. He explains that:
From the beginning she'd been stronger, tougher and braver than he ever was. At first it had embarrassed and shamed him, but he loved it in her so much that he got over it. (17.3)
If Trina were given more face-time in this book, we'd probably be able to draw a clear connection from her to Teresa (who, by the way, is Deedee). Trina is much braver than most of the dudes we see in the book, and if she weren't taken hostage she probably would've been kicking butt and taking names along with Alec and Mark.