You've just got to have a sense of respect for the person you have children with. Anger doesn't help anybody. Ultimately you have to say forgiveness is important and honoring what you had together is important. But it's easy to say and harder to do.
The first thing I do when I start my day is I get down on my hands and knees and give thanks to God. Whenever I go outside of my house the first thing I do is stop at the church.