I never felt so jealous of any wife of Messenger of Allah ﷺ as I did of Khadija because Messenger of Allah ﷺ used to remember and praise her too often and because it was revealed to Messenger of Allah ﷺ that he should give her (Khadija) the glad tidings of her having a palace of Qasab in Paradise .  

أَنَّهَا قَالَتْ مَا غِرْتُ عَلَى امْرَأَةٍ لِرَسُولِ اللَّهِ ﷺ كَمَا غِرْتُ عَلَى خَدِيجَةَ لِكَثْرَةِ ذِكْرِ رَسُولِ اللَّهِ ﷺ إِيَّاهَا وَثَنَائِهِ عَلَيْهَا وَقَدْ أُوحِيَ إِلَى رَسُولِ اللَّهِ ﷺ أَنْ يُبَشِّرَهَا بِبَيْتٍ لَهَا فِي الْجَنَّةِ مِنْ قَصَبٍ  

I never felt so jealous of any woman as I felt of Khadija, for Allah ordered him (the Prophet ﷺ ) to give Khadija the glad tidings of a palace in Paradise (for her).  

مَا غِرْتُ عَلَى امْرَأَةٍ مَا غِرْتُ عَلَى خَدِيجَةَ وَلَقَدْ أَمَرَهُ رَبُّهُ أَنْ يُبَشِّرَهَا بِبَيْتٍ فِي الْجَنَّةِ  

Never did I feel jealous of any wife amongst the wives of Allah's Apostle ﷺ as I feel in case of Khadija (though I had never seen her), for he praised her very often.  

مَا غِرْتُ لِلنَّبِيِّ ﷺ عَلَى امْرَأَةٍ مِنْ نِسَائِهِ مَا غِرْتُ عَلَى خَدِيجَةَ لِكَثْرَةِ ذِكْرِهِ إِيَّاهَا وَمَا رَأَيْتُهَا قَطُّ