Proverbs 5 deals with the ugly truth of adultry.
The long and the short of it is this: stay away from another man's wife and love your own wife. Verses talk about the respect you'll lose if you cheat on your spouse, and having children by another woman is like being raised by strangers.
To go down the dark path of being unfaithful to your spouse is like being eaten alive by a dreaded disease. Soon, you'll be on your deathbed, wondering why you did what you did.
Love your wife. Your spouse. This is the one you married and said vows to. Be faithful. Be honorable.
Being caught in the ways of wicked men will lead you to a lonely grave.