There is a common misconception that an annulment is a Catholic version of a divorce (see this question). However, this has made me wonder: is it is possible to get a divorce within the Catholic church, rather than an annulment? To put it another way, is it possible for a marriage in the Catholic Church to end before death in a way other than annulment?
Valid, consummated marriages of the baptized are indissoluble.
Can. 1141 A marriage that is ratum et consummatum (ratified and consummated*) can be dissolved by no human power and by no cause, except death.
*This means "the spouses have performed between themselves in a human fashion a conjugal act which is suitable in itself for the procreation of offspring, to which marriage is ordered by its nature and by which the spouses become one flesh." (Can. 1061 §1).
Non-consummated marriages of the baptized can be dissolved.
One way a valid (ratified or ratum) marriage between two baptized persons or between a baptized and non-baptized person can be dissolved is if it is non-consummated (ratum et non consummatum) and
- one makes a solemn religious profession
- one or both parties seek a dispensation from the Apostolic See (Petrine privilege).
See: Can. 1142
Marriages of the unbaptized can be dissolved if a spouse converts.
But if the unbeliever depart, let him depart. For a brother or sister is not under servitude [i.e., of the marriage bond] in such cases. But God hath called us in peace.
This can occur, for example, when one spouse converts to Catholicism but the other spouse "does not wish to cohabit with the baptized party or to cohabit peacefully without affront to the Creator" (Can. 1143 §2).