Is one obligated to fulfill a vow to fast every Thursday for life, and what is its legal ruling in cases where it conflicts with circumstances such as menstruation, marriage, or illness? Does the hadith "There is no vow concerning that which one does not possess" apply to it?

Abstract:

Whoever vowed to fast every Thursday must fulfill it. If she is unable to do so due to illness or severe hardship, as determined by a physician, she is permitted to forgo it and offer expiation with an oath-breaking atonement (kaffarat yamin (definition)). Menstrual days are excluded from the vow and do not require making up. However, if she misses fasting due to illness, she only needs to make up the missed days. If she misses fasting without a valid excuse, she must make up the missed days and offer an oath-breaking atonement. She must make up the days she did not fast along with an oath-breaking atonement. Neither the father nor the husband can prevent her from observing a vowed fast if the vow preceded the husband's right. The oath-breaking atonement consists of feeding ten poor people, or clothing them, or freeing a slave. If she is unable to do so, then fasting for three days. If fasting would harm her, the atonement is waived.