I wasn't married but as of recent I was in a relationship that ended badly and in my heart I know it was because someone else had entered the picture. Worse feeling in the world. Being unfaithful to your spouse is the absolute worse pain in the world to put upon someone else. Don't do it it's just not worth it in the end. You will lose everything including your self respect. The word "Cheat" speaks for itself.

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Missy