DEAR AMY: My wife and I are divorcing after 23 years of marriage. I am moving out soon. We have a 21-year-old son. I talked with him about it, and while he’s angry, he says he understands. The problem, however, is that my marriage was bad for a very long time, and I fell in love with another woman. My wife refers to me as an adulterer. She has said this to my son. How can I help him understand that I am not an adulterer? I want to have a great relationship with my son; I never want to leave him, but his mother has somewhat poisoned him. How do I explain things to him? – No Longer Lonely in Lon…