How Did I end up as her husband?

  Character is like a book, living with people, everyday opens a new page. I have read my wife's page and I expect something new every single day. All my life I have worked so hard to provide for family. I got married at 45, my first child is just 10 years old. I didn't marry on time, I was busy making all the money in the world.
After making money I decided to get a wife from my village, which I did. She was pretty and 25 years younger than I was. We got married and I took her to the city where I lived, she was the best thing that happened to me then. She bore me a son, I continued to work hard to enable me provide for my family.
Barely 2 years in the city, my wife changed into someone else. All of a sudden, she stopped preparing my meals and doing all the duties of a wife. She only cared about herself and son, she neglected me as her husband. I prepared my own meals, sometimes I would eat where ever I found myself before going home, I even washed my own clothes. All my wife did was go shopping and hanging out with her friends. I wanted more than just being married, there was no friendship in our marriage. I decided to find happiness outside.
This search for happiness made me chased after anything in skirt. I had enough money to spend on women and I did spent on them. My wife would turn the house upside down, threaten fire and brimstone because of my infidelity but she did not change her ways. The most annoying part of it all was she squanders money without knowing where the money came from and totally forgot her background before she married me. I got used to living my life as if she never existed but still provided for my family. I never wanted to think about my wife having an affair  even though I was having more than one affair. I was not enjoying my life like that, at my age I 'm supposed to live with my family happy together instead of chasing women like a 20 year old boy who wants to explore the world.
I do not want to divorce my wife for the sake of our son, all I need is to be a happy man. How do I go about it?