If you looking for a Catholic Internal Forum for Marriage, than I would recommend that you seek out a pastor who can direct you to the priest in charge of the marriage tribunals in the diocese where you are living. That is where the the internal forum for marriages begins.
The Vatican has recently published the following article on the subject: Note of the Apostolic Penitentiary on the importance of the Internal Forum and the Inviolability of the Sacrament Sacramental Seal.
The priest in charge of the Marriage Tribunal, is to be considered an expert on the topic of marriage and all related issues. What is brought up to him is immediately considered part of the internal forum and must be held in secrecy.
The jurisdiction of the internal forum deals with questions concerning the welfare of individual Christians and with their relation to God. Hence it is called the forum of conscience (Forum conscientiae). It is also denominated the forum of Heaven (forum poli) because it guides the soul on the path to God. The internal forum is subdivided into the sacramental or penitential, which is exercised in the tribunal of penance or at least is connected with it, and the extra penitential forum. Causes concerning the private and secret needs of the faithful can often be expedited outside the sacramental confession. Thus, vows may be dispensed, secret censures may be absolved, occult impediments of matrimony may be dispensed outside of the tribunal of penance. The internal forum deals therefore directly with the spiritual welfare of the individual faithful. It has reference to the corporate body only secondarily, in as much as the good of the whole organization is promoted by that of the individual members. Owing to the nature of the civil state and the end for which it was instituted, it has no jurisdiction corresponding to the ecclesiastical forum of conscience.
Sacramental and non-sacramental internal forum
Within the internal forum a distinction is made between the sacramental internal forum and the non-sacramental internal forum, according as matters are decided in the sacrament of Penance, and thus additionally protected by the Seal of the Confessional, or outside of the sacrament.
Thus the name of the parties in a marriage contracted in the external forum are noted in a public register, but a marriage celebrated secretly is to be noted instead in a special register kept in the secret archive of the diocesan curia.
Sometimes power of governance is given for the sacramental forum only: in each diocese a priest is to be appointed who has the faculty, which he cannot delegate to others, of "absolving in the sacramental forum outsiders within the diocese and members of the diocese even outside the territory of the diocese from undeclared latae sententiae censures not reserved to the Apostolic See".
In the Roman Curia, the Apostolic Penitentiary has jurisdiction for matters of the internal forum, both sacramental and non-sacramental, but in some instances its decisions hold also in the external forum, as when, unless it states otherwise, a dispensation that it grants in the non-sacramental internal forum from an occult impediment to marriage, is sufficient even if the occult impediment later becomes public. - Internal and external forum
It is always a poor idea to seek personal advice though the internet. Thus I recommend you talk to the priest in charge of the Marriage Tribunal in your area and seek insight from him. Questions posed to him are considered part of the internal forum and thus are considered questions of conscience. If he can not get you your answer (which I find doubtful), he will be able to point you in the direction necessary.