Is it obligatory to read the two vowed parts of the Holy Quran after the departure of the woman for whom one vowed to read them daily upon her return, then they separated again?

There is no obligation to fulfill a vow (nadhr) that was intended for a gathering from which there would be no dispersion thereafter, due to the precedence of the specific reason (sabab) over the general wording (lafz) that it contradicted. For, according to a number of verifiers (muhaqqiqin), the consideration is given to the specificity of the reason, not the generality of the wording. And by analogy, if someone swore an oath (halaf) concerning something for a certain reason, and then that reason ceased to exist, then what he swore about does not apply to him.