My Boyfriend Told Me Something Disturbing

I've been seeing someone for almost six months and we haven't slept together and he wouldn't sleep over. I was starting to think he really wasn't into me but he finally agreed to spend the night with me. We started to try to have sex, but he started to have an anxiety attack. I asked what was wrong. I knew he was a virgin, but I didn't think it would lead to such bad anxiety. He told me he lied about being a virgin. When he was in foster care his foster parents stole his virginity. The parents would rape all the kids. Both the mom and dad. He was 7 when it started and didn't get out of it until he aged out. He thought he could handle having sex and he's sorry that he isn't pure for me. I have never been in foster care and this disgusted me. I hugged him and told him whenever he is ready just let me know. He felt really embarrassed. I have never been sexually assaulted before either. I just .. can't imagine this type of pain...