No, it's not just you. I also get triggered by things that other people might find trivial, and it can put me into autistic shutdown when I come across them. In fact, it happened to me today, right here at Susan's, and I'm still not fully recovered.
You're entitled to feel upset, and I understand your reluctance to confront your friends. These things tend to escalate when they try to defend the indefensible and you could wind up feeling worse.
If you think you need to say something, have you considered responding in an oblique way? Such as by mentioning a celebrity who has been through something similar to you, without alluding to yourself? I can't think of any off the top of my head, but you could post something like 'well, it sure ruined the friendship of Jane Doe and Joe Bloggs, when he forced himself on her - and there's nothing funny about that'. That could get the message across without outing you.