Question

My husband and I are currently going through a divorce. He has refused to give up his latest affair partner. We have six children (2, 4, 14, 15, 20, 20). I just found out that my husband introduced my two youngest to his affair partner without my knowledge. We were told in mediation that introducing the affair partner to our children prior to our divorce being official was unacceptable. We were told that all parties should be involved as to when, where and how the introduction was to take place. He disregarded and ignored this advice completely. I wanted to be able to prepare myself and my children ahead of time. Not telling me was intentional on his part. Now he wants my teenagers to meet this woman and her 10 year-old son. They are not interested in doing so, and he is convinced that I am persuading them in not wanting to meet her. They are having a hard time with the consequences of my husband's choices and do not want to spend time with him and his affair partner.

What, if anything, can I do about this situation?