The Duchess is a very sincere and devoted catholic.... knowing that her marriage was annulled so didn't exist in the eyes of the Church must be devastating for her !
I can't speak for the Duchess directly, but can only convey my own experience.
Because annullment says that at the time of the marriage, there were flaws that rendered the marriage invalid, anullment actually came as a tremendous relief to me. What it meant was that, no matter what I did, no matter what course of action I took or did not take, the marriage was never there. There was nothing to try to "save," no course of action that would have rendered it valid. That although I entered into the marriage in good faith, the marriage simply did not exist because of a serious flaw at its very outset. And so, it was a complete relief to know that no matter what I did,
I could not "save" a marriage that did not exist.
We don't know the grounds for the annullment for the Duchess. I can tell you that the Church recognizes a number of grounds that render a person unable to give free consent, because of the lack of understanding of the nature of marriage. For instance - and may I say in advance that
I am not saying this in the case of the Duchess - suppose a young woman had been severely sexually abused by her male parent? Would she truly be able to understand the nature of the marriage bond? Or would it take a long time and some very serious introspection to understand that? Could she give free consent to marriage when she had been taught an unnatural and unholy way of relationships between men and women?
Suppose a young man came from a home where philadering was rampant. Would that young man understand the nature of the marriage bond? Could he give consent to a marriage when he lacked the understanding that marriage means fidelity?
Suppose that either of the parties were alcoholic or had drug dependency issues. Under the law, they aren't even capable or legally allowed to drive an auto under the influence. Can they "defog" enough to understand the marriage bond? Or has their view of the world become so skewed that they cannot comprehend marriage? Are they looking for a savior to rescue them from the dependency?
We don't know.
What I can say is that, instead of devastation at the receiving of the annullment, I felt a sense of peace and freedom that I can't begin to express. It was as though a loving hand had placed itself on my head and said to me "My daughter, I know you tried. It was not in your power, to save something that never was. You are released."
Again, I wish this for the Duchess, and it is my sincere hope that the Count of Paris has sought this out for his spiritual peace as well.
In a graceless world, it can be an act of grace.