I don't think that is why it is there though. I really don't. The type of character who leaps to mind when you read about someone who is in love but rejected because they are too monstrous, especially at that time, would be male. Not to sound like a broken record, but phantom of the opera or beauty and the beast.
With
very few exceptions, the type of character that leaps to my mind is almost invariably female.
(Take a look at fairy tales. Snow white is good and beautiful. The stepmother is not as beautiful, so out of jealousy, she becomes evil, murderous, and ugly when she disguises herself. Cinderella is good and beautiful. The stepmother and stepsisters
start out as evil bullies.)
If "at the time" they would be male, that was because of the prevailing sexism of the times where men were usually the main characters in the story and the woman was there to be the love interest.
There are plenty of examples of male characters who suffer that kind of affliction. As another poster pointed out, her curse mirrors the curse of Dominic D'Honaire, who is cursed to become ugly and unappealing to any woman who becomes attracted to.
But he's got a lot more going for him. It is repeatedly shown how he manipulates others, and his political machinations have been written about in far greater detail than Jacqueline's. Hell, he even has his Obedient, while
she doesn't have full control over all the wererats.
And, in the Gazetteers, he has found a woman who is willing to pretend to like him. That didn't stop him from being awful to people in general, unlike Gabrielle, who is written as being
much less evil now that she has Matton.
It is also worth noting both had paternal figures named Claude. Both have vaguely French domains. The mirroring is probably intentional.
More likely they were written either by people who liked the name Claude because it's very French (and they either didn't notice or decided it was OK for them to have two dead NPCs with the same name) without sounding sexy or pretentious, or they wanted to have a nod to actor
Claude Rains but already had two werewolf domains (Verbrek and Arkandale) and couldn't think of a good Invisible Man domain. After all, they only had a tiny handful of non-Darklord NPCs in the original box.