If you satisfy a women adequately in the key areas of life she will look up to her man and remain loyal.
Just shooting from the hip here... ensure the following to pretty much guarantee they won't stray.
1) Make her cum hard once a week.
2) Be a leader she can admire.
3) Always maintain the dominant position - women take pleasure in being put in their place after they attempt such foolishness as a shit test. I pass all shit tests with flying colors, and will gently rub her nose in said shit if I feel necessary.
4) Be easygoing and forgiving. Everybody fucks up now and then. Yelling and complaining too much will break her spirit.
5) Provide for your family. Do something interesting with your career.
6) Be mindful of your mission and less mindful of her needs. If her needs or wants conflict with yours, don't fucking budge. As crazy as it sounds, they secretly enjoy being put in their fucking place every now and then.
7) Don't fucking clean. Hire a cleaning person if necessary. Cleaning the house will take the tingles away for sure.
8) Practice random dread games a few times a year. She should realize that you have options open to you. Be a flirt right in front of her face. Believe it or not, this shit makes them angry and wet.
9) Lift fucking weights. No exceptions. Have muscles.
10) Incorporate random tempered dickhead level hostility every now and then. When she gets upset, end it and treat her good. This maintains the drama in her life that she so desires.
11) Be unpredictable
12) Show her love. Tell her at least once a week you love her and show genuine love.
If you do these things, every possible itch in her life will be scratched and she won't cheat. This assumes you married a decent woman and not a whore slut. If you married a cock carousel riding whore, there's a good chance she'll cheat no matter what you do. There's plenty of decent women out there. Even the decent ones will cheat if you fail to satisfy them.
the good ones won't cheat. If you fail to do so