I Need Advice on How To Handle a Situation...

I am a 20 year old college student who is home for the holidays. I was seeing an old friend last night and she invited another friend who went to high school with us. I had heard a lot about her but never met her. So we're eating dinner together and start talking about ex-boyfriends. She mentions she dated a guy and told me his name, and I panicked. As it turns out, her ex-boyfriend is the guy who molested me for years when I was younger. He's a few years older (as was the girl) and I'm not sure how to handle the situation. I was diagnosed with PTSD with the molestation being a contributing factor, and I'm not sure I can continue to be friends with her when she brings him up, but I don't want to tell her because I have never told anyone his name. I do want to continue being friends with her though. I'm just not sure what to do.