I don’t have anywhere else to complain to..

I work at an adult probation and parole office as a clerk, for my light duty post. I was previously a CO at a juvenile jail, so a lot of my coworkers were 21-27 age range. I recently saw an old coworker come in to report on sex offender day, and I was so angry and uncomfortable. He didn’t hurt a kid, but he did hurt a friend of mine. It’s just infuriating to see him laughing and joking with others, while she has to go to therapy twice a week for what he did. I know I shouldn’t be so angry, but I am. Just wanted to vent!!