Committing the sin of adultery is obviously evil, you don't need to be Catholic (or part of any religion for that matter) to believe this. Adultery destroys the trust that exists between two people who form the very fundamental unit of society. It also has terrible effects on the children of the marriage... Jesus stated that to "even look at another woman with lust" was a act of adultery! As God, he understands very well just how important and sacred the union between a husband and wife is. There's really no need to elaborate further, cheating on one's spouse or with the spouse of another is a terrible crime and an injustice to all.
So is adultery the only sin against the sixth commandment? The Church controversially teaches no. Sexual acts that may be considered in popular culture to be moral and acceptable are considered by the Church to be grave sins against chastity (a virtue everyone is called to under this commandment, no matter what their state in life). Basically, any use of the sexual faculty outside of marriage between a man and woman is considered illicit.
A great book on the Catholic view of sexuality is titled: Good News About Sex and Marriage: Answers to Your Honest Questions About Catholic Teaching by Christopher West. It covers everything that one should know regarding this incredibly important topic. It is well worth the cost and time. Here's another resource that may be helpful: Sexual Morality.
Questions to consider: Do we try to mold God so that he fits into our ideas and lifestyles, or do we allow God to mold us? Are we not sinners who do not have all the answers and may in fact be clouded in our understandings? Are we blocking God's grace in any way as he tries to conform us into an ever higher state of being, a higher state of love?
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|part 3, section 2, chapter 2, article 6|
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