As Fr. Arthur McGowan commented in a previous response, there is no “taboo” here. These situation occur in every parish and are handled the same way. As long as the to-be-marrieds are eligible to marry each other, there’s no canonical impediment, and they are in a state of grace (having repented previous sins with a firm desire of amendment) they really can’t be denied marriage. None of these situations are, on the face of them, in violation of Canon Law.
None of these situations are, on the face of them, in violation of Canon Law.