Sunan At-Tirmidhi

Narrated 'Aishah:""I did not envy any woman as I envied Khadijah - and the Messenger of Allah (ﷺ) did not marry me except after she had died - that was because the Messenger of Allah (ﷺ) gave her glad tidings of a house in Paradise made of Qasab, without clamoring nor discomforts in it