The tendency to find fault often gets in the way of prayer. I do not want to discourage anyone from trying to be the perfect parent and the best imaginable example to your kids. Please do. Put all your heart and soul into it --- but in the end you will fail. And so will your spouse. Your only hope is in the Lord Jesus Christ. The best parenting advice I have heard came from a man who had prayed his daughter back from rebellion. He said he had three words for people who asked his advice: 1. Pray. 2. Pray. 3. Pray some more.
Of course this assumes that you have such a standing before God that you can pray. Humbling yourself before him will secure that, regardless of what other failings you have.