You shall not commit adultery. It mostly means that if you follow the God who revealed himself to Moses and Abraham and then revealed himself ultimately in Jesus Christ, then you will not have a sexual relationship with somebody that you are not married to. As a woman, I am only allowed to have sex with my husband. Before I married him, I was allowed sex with no one.
But adultery goes deeper than that. Jesus said in Matthew 5 that I only think sexual thoughts about anybody other than Tim, then that is the same as committing adultery. Long before I knew Tim, I had those thoughts. I am an adulteress on the inside. It is the same as being an adulteress on the outside.
How does this tie in to co-dependency? How do love affairs start? If I was to try to help another person with her marriage or child-raising and it was destroying my relationship with Tim, would that not be an emotional affair? I believe so. I remember when I was a teenager and AOL instant messenger was still the thing, a married man would sometimes confide in me about his struggling marriage. I had a penpal relationship with him before he met his wife at the time and married her, but I was too young to realize, that that is kind of an emotional affair. Sure I want to help him and give him advice and pray for him, but to let a married man confide in me about his personal life is a kind of affair.
Women especially need to be careful when they try to help people, whether men or women, outside of their family. God calls us to be witnesses and to love our neighbors, but we also must love God first and our husbands second. I love other people, but I cannot help them in such a way that it would endanger my relationship with Tim or with God. It's just something to think about.