When divorce is imminent is it worth using a mediator, rather than go to court straight away?

We have been married for almost 15 years, have two children (son 13 and daughter 11). It recently came out that he has been cheating on me with a girl from work for nearly 8 years. It was our son who found out from text messages between them. He wants to keep the house and not pay anything towards our/his children's upbringing.