All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His slave and Messenger.
If you mean that a person says to his wife: "I swear by Allaah, if you do such and such without my permission, I will leave you, or that our life will not continue.", then if she does that matter without his permission, he is not obliged to divorce her, but if he does not divorce her, he breaks his oath. In this case, he is obliged to expiate for breaking his oath; for more benefit on expiation, please refer to Fatwa 102811.
Finally, it should be noted that one should avoid swearing too much without a need, as this may lead a person to hardship, and Allaah ordered us to preserve our oaths. Allaah Says (what means): {But guard your oaths.}[Quran 5:89]
Allaah Knows best.