Re: Desperately want to end wife's affair
You should put some effort into finding out who this guy is, where he lives, etc. Find his girlfriend and tell her about the affair.
Tell her family about the affair as well as ask them for help in ending the affair and repairig your marriage. Telling your family is generally a good idea as well.
As for the book.. it gives a lot of ideas about how to end the affair as well. It covers the idea of a no-contact letter an has the basic letter in the book.