I messed everything up help

I recently went through something online that left me feeling shocked, confused, and very upset. I downloaded Reddit for the first time, and I wasn’t talking to many boys at all. The first boy who messaged me was the one I ended up talking to (for 4 days ). He told me he was a young university student, and because he seemed normal and friendly, I believed him. While we were chatting, he started talking in an inappropriate way toward me. I did not talk inappropriately to him. I didn’t encourage it, and I didn’t expect the conversation to go in that direction. At some point, he suddenly stopped replying, so I assumed he had fallen asleep. I sent him a simple “good night” message and didn’t think anything was wrong. About twenty minutes later, I received a message from the same account, but this time it wasn’t him. It was his wife. She told me that they were married and that the man I had been talking to was her husband. I was completely shocked. I had no idea he was married, and I definitely didn’t know he had a wife who could see the messages. I felt embarrassed, betrayed, and confused, because I had trusted what he told me about himself Since then, I keep thinking about the situation and blaming myself, even though I didn’t do anything wrong. I didn’t know he was lying, I didn’t know he was married, and I didn’t know he had children. He was the one who acted inappropriately and hid the truth from me. I’m still trying to understand why someone would lie like that and put me in such an uncomfortable situation.