Satan hates the good relationship between husband and wife-Imaam Ibnul Qayyim
Narrated Jabir (radiyallaahu-anhu) that Allaah’s Messenger (sallal-laahu-alayhi-wasallam) said: Iblis places his throne upon water; he then sends detachments (for creating dissension); the nearer to him in rank are those who are most notorious in creating dissension. One of them comes and says: I did so and so. And he says: You have done nothing. Then one amongst them comes and says: I did not spare so and so until I sowed the seed of discord between a husband and a wife. The Satan goes near him and says: ‘You have done well. A’mash said: He then embraces him. [Saheeh Muslim. Number:2813]
And due to the fact that this bond (between husband and wife) is from the most beloved affairs to Allaah and His Messenger, it is from the most hated affairs to the enemy of Allaah (i.e. shaytaan). Therefore he hastens to split two people who love another for the sake of Allaah.
[Source: Rawdatul Muhibbeen Wa Nuzhatul Mush-taaqeen. Page:188]