Ahhhh... your post...
I am working on something with some of my peers (your peers too) that will hopefully someday address this specific question and provide help for this kind of pain.
Infidelity is torture but you are here on these boards because you know that this is a unique situation, one that is nonetheless full of heartbreak and pain, for everyone involved.
As far as "getting over", it's not what happens. It is more like getting past, or seeing past. It is more like seeing the whole picture and putting everything in its relative space. It is more like seeing the actions of another person as independent from you. It is a long process that often times feels cyclical and tortuous.
I don't know anything about your situation or what is currently going on. I will tell you what our couples therapist once told me: You have to together decide if this is just one chapter or the whole story.
Please feel free to pm me. You are NOT alone. You are heard and in the company of some really fabulous people who are struggling to support someone they love who has hurt them in really profound ways.