First, I want to say, I am glad you were brave enough to come clean to her.
A small 2x4. I have always said there are more infidelities in a marriage than cheating. This is one of them. Just like you wouldn't want her to justify an A, please don't even try to justify this or place any emphasis on justifications because of the timing of where your relationship was because of her infidelity. You wanted total and complete transparency from her and you weren't giving her the same.
Honestly, she reacted way better than expected or I imagine I would. She sounds like even though upset, she is being very supportive. I would expect she is going to want complete financial transparency now. I would also suspect you are going to give her that. This may take some days to settle in for her. She may have waves of anger. I would expect and understand that too.
This will truly test the strength of your reconciliation. For both of you, just not her commitment. It's a lesson and a blessing in a way, and I hope you find a way to work through this as a couple.