It will set everything back when more truth is learned, that is normal. It is dday all over again.
Are you going to an IC ? It might help you work through the details you have learned.
Is this a deal breaker ? For some of us, especially after going through infidelity, there are no second chances.
He broke your trust sometimes that is a deal breaker and you have to decide if you want to continue forward with him. Not an easy decision when he's showing remorse.
Seek out an IC or Pastor for help to find some clarity.
Big Hugs and you aren't alone !