from canon law–if the wayward spouse is repentant, forgiveness and readmittance to the common conjugal life is earnestly recommended, but the wronged spouse does have the right to separate. This does not invalidate a valid marriage, however. If the marriage was valid prior to the infidelity, the separated spouses are not free to remarry while they both live.
*Art. 2.
SEPARATION WITH THE BOND REMAINING
Can. 1151 Spouses have the duty and right to preserve conjugal living unless a legitimate cause excuses them.
Can. 1152 §1. Although it is earnestly recommended that a spouse, moved by Christian charity and concerned for the good of the family, not refuse forgiveness to an adulterous partner and not disrupt conjugal life, nevertheless, if the spouse did not condone the fault of the other expressly or tacitly, the spouse has the right to sever conjugal living unless the spouse consented to the adultery, gave cause for it, or also committed adultery.
§2. Tacit condonation exists if the innocent spouse has had marital relations voluntarily with the other spouse after having become certain of the adultery. It is presumed, moreover, if the spouse observed conjugal living for six months and did not make recourse to the ecclesiastical or civil authority.
§3. If the innocent spouse has severed conjugal living voluntarily, the spouse is to introduce a cause for separation within six months to the competent ecclesiastical authority which, after having investigated all the circumstances, is to consider carefully whether the innocent spouse can be moved to forgive the fault and not to prolong the separation permanently.
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Can. 1154 After the separation of the spouses has taken place, the adequate support and education of the children must always be suitably provided.
Can. 1155 The innocent spouse laudably can readmit the other spouse to conjugal life; in this case the innocent spouse renounces the right to separate.*
Sometimes, however, the nature of the infidelity and the unfaithful spouse’s testimony about it indicates that the unfaithful spouse had never intended to give true and unequivocal matrimonial consent. In that case, a marriage thought to be valid may have been invalid, because of the hidden intention of the unfaithful spouse.