@andateika and @Mae My take on it was when he confronted the guy about what he said about his sister, he asked Boris not to say anything. Boris said it had nothing to do with him. Tracey was standing just around the corner and heard him. I interpreted her jumping in front of his car as a "well you didn't help me cause it had nothing to do with you, so i'll make sure you understand my death has something to do with you" kind of thing. (not sure if i expressed that properly). I think she had already planned to kill herself (which happens with many rape victims). The reason she chose to jump in front of Boris' car was because she wanted him to know that while he may have not raped her, he did nothing to stop it, which made him just as guilty in her eyes.

Who is tracy again??