The Catholic Encyclopedia (see here) says the following:
- Adultery of One of the Parties
The innocent party always retains the right in justice to recall or to demand the return of the guilty party. If the innocent husband or wife wishes to give up this right forever, then he or she can enter a religious order, or he may receive Holy orders, without the necessity of consent on the part of the guilty wife or husband who has been dismissed, or without any further obligation being imposed upon this party (III Decretal., xxxii, 15, 16). The guilty party can, however, proceed to the religious life or to the reception of Holy orders only with the consent of the innocent.