My point was that she would be divorced. To the best of my knowledge Catholics do not believe in divorce ergo she would still be married. Being married she could not marry anyone else.
This is correct. Her marriage would be presumed valid. The marriage could be investigated by the Catholic Church for validity.
The only alternative is that the Catholic church does not recognize the marriages of anyone not married in the Catholic church. However if that is the case here presumably there would also be no need for an annulment.
No. This is not the only alternative. The Catholic Church presumes all marriages are valid. However, a marriage may-- upon investigation-- be shown to have not been valid. This would be true if there were an impediment or a defect in consent or intent.
Am I missing something here or is an “annulment” merely a euphemism for recognizing divorce in Catholicism?
No, a decree of nullity is not a divorce.
Two baptized persons who marry validly contract a marriage which is indissoluable. It is also a Sacrament by virtue of their baptism. A marriage can be investigated, and if it is found to have a defect
at the time the vows were exchanged (a defect of consent or intent or an impediment of church or divine law) then their marriage would be declared null. It was never valid.
A simple example of this would be the groom showing up at the wedding drunk-- consent is impaired. Another example would be if the couple were forced into a “shotgun wedding” by parents-- consent is not freely given. Those are just two example.
When two persons who are unbaptized are married, their marriage is a good and natural marriage. It is not a sacrament. And, it
is considered dissolvable under Church law-- in favor of the faith. Meaning if an unbaptized person converts and is baptized, they may have their marriage dissolved “in favor of the faith”. Meaning, they are not bound to the unbaptized spouse. This is under only specific circumstances outlined in Church Law.
Since you don’t have a backgroun in Catholicism, this may be more than you wanted to know… but bottom line a decree of nullity is not a divorce, and all marriages are presumed valid unless proven otherwise.