Wasn't sure where to put this. It is an extremely awkward situation, and I really want to know what to do for the best.
When we were in our late teens, my sister's best friend was gang raped by three boys we had grown up with and were supposedly friends with. She reported it to the police (who were great) had the necessary medical examinations, made a statement etc. However, she decided not to proceed with things, so the boys were never arrested and there were never any consequences for them. In fact, the only people who knew about the attack were the girl, her mum, me and my family, and the police. The attackers carried on their normal lives.
Over the years, my sister and this girl drifted apart. We no longer see her. My sister and I had both moved form the area we grew up in some years ago, too, so didn't see the attackers either. However, recently, we have been to two parties of old friends where the attackers have also been invited. It has been extremely difficult to know how to deal with them. So far we have managed to avoid talking to two of them. One of them came over to say hello and I was extremely cool with him and thought he had got the message, but he later requested me as a friend on facebook and sent me a message about 'the good old day's. Bear in mind, these men (as they are now grown up men in their 30s) do NOT know that we know what they did.
We have got a good childhood friend's birthday coming up and I know they will be there. How do me and my sister play it? We have discussed the options at length - not going to the party (would be very upsetting for our friend), blanking them completely (they would want to know why), letting them know discreetly that we know (how? Would this really work?). personally, I feel like screaming 'RAPISTS!' in their faces (I had months and months of extreme anger and rages at the time this happened and fantasisied about doing all manner of awful things to them ).
What would you do?