am I in the wrong for being upset at my husband?

So basically to sum it up, 2 days ago I found out my husband made out with his ex, tried sleeping with another female, and talked to another one of his ex’s at a party. This was a year and a half ago while we were dating. He never told me. I had to find out and then when I questioned him he finally came clean. We are married now. I’m so upset with him but I don’t know what to do.. he lied to me for that long. We have a son together. Should I divorce him or should I just leave it alone since we weren’t married then? Please help. I don’t know what to do. 😢