I have a book I'd like to recommend. It's helped me tremendously and I'm so glad I've read it - several times! My first husband cheated on me and I applied the principles of it. I could have had him back but decided I did not want to reconcile after his affair. It's called Love Must Be Tough (Help for families in crisis) by James Dobson. It addresses infidelity like I've never seen! I have applied what I've learned there with good success. My only issue is that I wish it had more specifics on what to do/not do. That's where DB is a little better in discussing GAL and 180s...but the Dobson book is harder on affairs!