Hang in there! You have an advatage over a lot of us on this board, as many of our spouses have not talked or agreed to "Work" things out.
I would say GIVE IT ALL you've got if you really think she is serious. She must be willing to totally remove herself from the OM and also be commited to never hurting you again.
I have done a lot of praying, asking God to give me the strength to forgive. It's a very difficult thing to do, but it can be done with time and effort. I owe my sanity to answered prayers.
Wouldn't we all love to just "forget"? Unfortunatly we probably never will. If you dwell on it, you'll never be able to completly forgive her.
You will both need assurance/love and support from each other, to help you get through this difficult time.