Pretending you aren't upset about this won't help your son. It would be better to admit that you are crushed (that might allow him the opportunity to admit the same). Then you can assure him that you love him, and you will get through this together.

DON'T make your son your confidant, though. It's not his job. And hard as it might be eventually, don't say anything bad about his mother. He will figure it out on his own.

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