I am very sorry to tell you this, but he is not going to change. This author went through the very same, and worse:
https://www.amazon.com/dp/1693393220
Recognize the warning signs now and act. It's very sad that people can be that way, but once you learn of something like that, you start to notice other things that they have been lying about as well. You deserve better than that! Best of luck to you.
Autumn: Since you said you are not going back to him, if you want more than just a separation and want a divorce, see a divorce lawyer ASAP. Protect yourself financially so he won't take YOUR money. Get your own bank account and cancel all joint credit cards/dept. store cards if you have them. I would never trust anyone like this. Sorry this happened - it's really shady!