Here's the problem:
Very few priests or bishops accept Church teaching about this issue. They want an Orthodox solution, based on sacramental economy.
Because they can't get that, they manipulate the system the Roman Church has created to deal with this problem.
Make no mistake, it IS a problem-one which I know well.
I know. I have an annulment and have not remarried. Jesus didn't have any annulment rules. You were either married for life or you weren't. They argue about the "except for adultery/fornication", but let's not go there.
St. Paul, I believe, talked about couples where they couldn't live in peace over religion or whatever, and said let them depart, but he was silent over whether the parties involved were free to enter into a new marriage covenant.