2,827. The Two Types of a Wife's Vows

Hilchos Nedarim 12:2

The difference between vows of self-affliction and those that affect the relationship is that when it comes to vows of self-affliction, he annuls for both himself and others; as far as vows that affect the marriage, he annuls for himself but not for others.

Hilchos Nedarim 12:3

Pursuant to the previous halacha, let’s say that a woman made a vow not to eat meat. Her husband can annul it, which will enable her to eat meat even if she later marries someone else. If she prohibited herself to have marital relations with any man, he can only annul the vow vis-à-vis himself. However, if he dies or they divorce, she is still prohibited to engage in sexual relations with all other men. The same rules apply in all comparable cases.