Is it permissible to send a message to a young man to inform him of her return to her husband, and is she considered divorced after the divorce was made conditional upon her messaging any young man?

If a husband conditions his wife's divorce on her corresponding with any non-mahram young man, then if she corresponds with him, the divorce occurs. A woman's correspondence with a non-mahram young man is a reprehensible act and a sin, so what then if it leads to divorce? Therefore, she must fear Allah, cut off illicit relationships, and protect her husband.