AIO after partner cheated and caught through a scam?

So I found out my partner was cheating after he was caught in a scam. I looked through my message requests to find messages from a scam person of videos/photos of him being on videochat with a "woman" (scam person) naked and doing things to himself. At the time I was in hospital with pre-term labour. I found the messages, they were sent to me in January. I confronted him and he said he knew it was a scam so played along, which I found absolutely weird. I told him I wasnt listening to his lies anymore and told him he needed to pack a bag and leave, AIO? should I of listened to his reasoning and believed it? I dont know what to believe anymore, he accused me of cheating the whole time we were togther and even while I was pregnant and in pain with his baby. I feel so betrayed and hurt