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 Long Island

Dear No Longer Lonely: In the shorter term, you should focus less attention on justifying or trying to redefine your behavior, and focus more attention on your son.

Please understand that any younger person when facing extreme change thinks: “But what about me?” Your son’s first concern is (and should be) more on his own happiness and future than on yours.

And right now, because of this break-up, your son has about 10 times more relationship challenges than you do.

He has to somehow navigate having a separate relationship with his angry, bitter and betrayed mother – and his liberated, self-focused and (I assume) abundantly happy father.

I’m trying to figure out what about your behavior does NOT constitute adultery. So perhaps you should simply cop to this.

I assure you that every spouse who has ever exited their marriage via another relationship has justified it by pointing to their own unhappiness.

But the order of marriage-exit is supposed to be: Decide to separate, move out, divorce, new relationship.

Do your best to create a lot of space for your son to say whatever he needs to say. Absolutely correct the record if the narrative has strayed completely from the truth, but invite him to ask you any question and answer him truthfully.

My suggestion is that you not criticize his mother for feeling betrayed – even if she unfairly lashes out. Her feelings are her feelings, and you should say only that you are sorry she is feeling so sad and you wish she wouldn’t draw your son into her sadness.

Do not fling your new relationship into his path, compare your new woman to his mother, or ask him to be happy for you.

Apologize to him for disrupting his life in this way, and assure him that you will always be in his corner, no matter what.

You can email Amy Dickinson at [email protected] or send a letter to Ask Amy, P.O. Box 194, Freeville, NY 13068.