For you, it happened last week.
He thinks he's put it all behind him.
You are suffering in this moment.
Take time to deal with this. I'm a fan of IC (Individual Counseling) for dealing with this. Don't make any big decisions until you have had some time to settle down.
It will likely take you months, maybe several months, to deal with this trauma.
Read a lot in the Healing Library. There's a link in the yellow box at the upper left of your screen.
If he really means "He said he did not say anything for 13 years because he wanted to spare me the pain and he feels that he loves me more than ever before because of this.", then he needs to step up and do what it takes to help you heal. He needs to take responsibility for what he did, and for helping you get through this.
ETA: (Edited To Add) There's a thread in the I Can Relate forum for those who found out years later. It might be helpful to see others who share your experience.
[This message edited by TrustedHer at 8:16 AM, June 4th (Wednesday)]
I'm so sorry. You can still have your bond with him, though I know right now it feels impossible. It will be hard, there will be triggers, you will feel vulnerable and angry and sad, but he can help you, and with reassurance and time and some counseling, you can feel even closer than before. However don't force yourself to stuff down your feelings because it happened in the past. It is still a loss. The rug has been torn away from your feet and the blinkers from your eyes. Suddenly you question everything. It's a betrayal even if he stayed. I hope he realizes you need to be able to talk about this and be given room to discuss and vent your feelings. And don't forget that you ARE loved and he did stay; I know it doesn't make the pain go away, but hang onto that if you can. There is a thread in the I Can Relate forum for those finding out years later that you may find helpful. It is not an easy matter of weeks or months to synths is ethics new information about your life. But have faith that you can do it.
You will be okay.