An Agent for Ulyssa — Patricia PacJac Carroll

Ulyssa Long has been a Pinkerton agent for seven years. She likes working alone. And is ruthless in solving the cases she's been given. She is surprised when she is called into the Denver office to take on Sam Paxton as her partner in training.
She refuses but is told that she can look for another job if she doesn't want to do as she's told.
Sam Paxton needs to prove himself as a good man to make up for his outlaw past. He's eager to learn, but Ulyssa is a beast of a woman. Oh, she's pretty all right, but meaner than a snake. He's met outlaws that were friendlier.
The case â€" Roy Allred, a wealthy rancher in southern Colorado, has a problem. His only child, a daughter â€" Trucilla, Rusty, Allred who is twenty-three years old, pretty, and in love with a man who Roy thinks is only interested in the ranch.
Ulyssa and Sam are to break up the young couple and protect Rusty from Chad Monroe. Well, all I can say is you'll just have to see what happened.