After a divorce, negative feelings are normal. While you should always have a space to vent and people you trust to talk to, be careful of what you say about your spouse in front of your children.
Even if the negative talk has some merit, kids should remain protected from it. When you or your ex-spouse talks negatively around your children, it can lead to parental alienation. Parental alienation can severely damage the relationships between parents and children.
Younger kids may feel guilty following a divorce, even if you say nothing about your ex or give the children a reason to feel guilty. Often, kids wonder what they could do to mend the relationship or think that they had some fault in it. If you consistently negatively talk about your ex, it can cause your children to feel guilt because of the relationship. Kids may feel guilty having a close relationship with their parents because of how each one thinks about the other.
Your kids relate to you and your co-parent. They know they are a piece of both of you and can internalize what you say about your ex and what he or she says about you. The kids may think they have something wrong with them too or may be prone to the same habits or personality traits that the other parent does not like.
If your co-parent paints you in a negative light or alienates you from your children, he or she has created an abusive situation.