the observance of the law in any particular case would cause special hardship which the lawgiver cannot be presumed to have intended, the person so situated is excused from obeying the law by an equitable interpretation of it. If, for example, I should incur serious risk of contracting some disease if I went out to hear Mass on a Sunday, I am excused from obeying the precept.
Such equitable interpretations are specially permitted in affirmative laws, not in those which make an act done contrary to them null and void. The common good requires that these should be observed even with grave personal inconvenience. And so the diriment impediments of marriage do not cease to bind even when they cause serious inconvenience in particular cases.