I've often said that one of life's most painful lessons is that we cannot change the past. Once we have done something we shouldn't have done or failed to do something we should have done we have to live with the consequences.
But don't misunderstand me! We may not be able to change the past, but we can change the future with God's help. That doesn't mean we can undo all the damage we have done, but it does mean we can set our lives on a new course, and begin to be a blessing to people instead of a problem. The Bible's promise is true: "If anyone is in Christ, he is a new creation; the old has gone, the new has come!" (2 Corinthians 5:17).
This is why I urge you to turn to Christ and commit your life to Him. God loves you; He loves you so much that Christ was willing to give His life for you. Ask Him to forgive your past and to come to live within you by His Spirit and He will.
Then ask God to show you ways you can overcome the hurts you may have caused your children. Let them know you love them, and that you are sorry for the past. I can't promise all the barriers will fall but with God's help you can encourage them not to make the same mistakes you did, but to give their lives to Christ and begin to follow Him.