EDV-
I read a great book that helped me alot in your situation
"How Can I Forgive You? And the Freedom Not To." By Janis Abrahm Springs who specializes in infidelity (though this book is not about infidelity). Her other book helped me immensely with healing from an affair also.
One of the most important things I learned is that I don't have to decide anything today.....I can wait until I feel all of the emotions that come up and give myself the space to decide. I felt a lot of emtions about this for a long time and for me "deciding" to forgive early on would have been me stuffing down my emotions.
In the end the drinking was a bigger challenge for me to recover from....I hope you are taking good care of you right now.