Uncertain about what to do about my kids father leaving his kids?? ~Please Read~?

You have to let him be a FATHER regardless of how you feel. He made a fatal mistake and apparently he decided to retaliate as a result of the separation. Your children shouldn't be deprived of a good father. Take care of you and learn from this experience. Go find yourself a good man but don't take away a good father. If he's a good father, why take that away from your children? Set your differences aside for your babies. Don't worry about that rag and what he's doing! He's NO longer your man which means he's NO longer a problem! LOL