All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad, is His slave and Messenger.
It is prohibited that a person tries to spoil the marriage of a woman by turning her against her husband, which is known in the Sharee‘ah as Takhbeeb. It was narrated on the authority of Abu Hurayrah that the Prophet said: “The one who turns a woman against her husband is not one of us …” [Abu Daawood]
The jurists held two opinions concerning the validity of the marriage of a man with the woman whom he turned against her husband (and caused her divorce); the majority of the jurists are of the view that the marriage is valid.
The Maaliki scholars, on the other hand, held that her marriage to him is invalid as a punishment for the sin of Takhbeeb that he committed, and that it is incumbent to terminate such a marriage in order to punish him with the opposite of what was his intention. However, the preponderant opinion is the one held by the majority of the scholars, i.e. that the marriage is valid. Although Takhbeeb is prohibited, yet if the marriage contract is conducted properly by fulfilling the conditions stipulated by the Sharee‘ah, then it is valid, and the Takhbeeb that preceded it does not render it invalid.
Allah Knows best.