Wife 30F just told me 30M she was SA by Ex while we were talking and becoming a thing. Did she cheat?

While I was deployed 11 years ago I had started talking to my now wife of 10 years. During my deployment after we had been talking for several months and agreeing to see each other when I got home, she had sent me a Snapchat showing her crying and saying he hit her. The he was her piece of shit EX. She said she was at a party and he had tried to have sex with her and she said no, so he hit her. This was what I believed for the last 10 years. Now as I was out of town the talk of bad things happening at sleepovers brought this up, to where she said she was sexually assaulted by this asshole. She told me that she went to the party with her best friend and ex and her and her ex started to hook up, but she remembered me and told him to stop in which he didn’t.

I understand I guess we really weren’t a legitimate couple, but I feel like it was a mutual understanding we were going to be. I want to be mad about that, but I am so pissed about what happened to her.

Thanks.