Find the name of a Book

#1

I was reading a " Son in law " style book, and I cant seem to remember the title of the book… in the book there is a chapter where the wife of the main character ( MC ) just told the MC she wanted a divorce cause her first love was trying to pursue her. During the confession of the guy pursuing the MC’s wife the MC paid someone to show on a projector all of the nasty things this guy had done. Then the wife of the MC is grossed out by the video and she walks away… Please help me find this book

#2

The The title of the story: I Will Marry You.