Since even the Church presumes a marriage to be sacramental until proven otherwise by a marriage tribunal, no one, including the spouses themselves, should be prejudging the sacramental validity of their marriage. If someone knows that he may be in an irregular status due to the circumstances of his marriage, what he should do is to seek to do what is necessary to regularize the marriage – especially if there are also circumstances that make preserving the marriage prudent (e.g., dependent children). If the marriage cannot be regularized, and there are sufficiently grave reasons for remaining married to the putative spouse (e.g., dependent children), one could choose to seek to live with the putative spouse as brother and sister.
