When a man declares his wife unlawful for himself that is an oath which must be atoned, and he said: There is in the Messenger of Allah ﷺ a noble pattern for you.
إِذَا حَرَّمَ الرَّجُلُ عَلَيْهِ امْرَأَتَهُ فَهْىَ يَمِينٌ يُكَفِّرُهَا وَقَالَ { لَقَدْ كَانَ لَكُمْ فِي رَسُولِ اللَّهِ أُسْوَةٌ حَسَنَةٌ}