You should behave with maturity. You should try to fill the gap between them. You should have a lovely behavior towards both of them. You should make them understand that both of them have equal role in your life.You should purposely arrange picnics or some other occasions where both of your parents have a chance to participate.
The best thing is to try to stay impartial. Be supportive of each parent, but don't take sides. If they ask you to take sides, just say no. Don't take it personally, either. It has nothing to do with you and everything with them.
First, do not pick sides or play favorites. Secondly, inform your parents that their problems are between them. They are not to criticize each other in front of you.
