I've read your profile.
1) Are you saying your W had an A with her therapist?
2) The feelings and thoughts you describe are pretty common for this soon after D-Day. You sound like you don't think you can ever heal from this hurt, and that can be a self-fulfilling prophecy.
3) You're not alone. The virtual world is different from the real one, but we know your pain, and we here to provide support. Just let us know what you need.
4) In the I Can Relate (ICR) forum, there are threads for Betrayed Men and for BS Questions for WSes. You might take a look there to see if those threads help.